Reliable Systems

I’m an engineer at heart. I worry about all the little details of how something works technically. When I can, I go for the overengineered solution every time. We recently needed to get a Microphone Pre-amp to USB device. Instead of getting the plastic MAudio unit that probably works just great I got the USBPre at twice the price. Why? Just look at that case, it’s awesome:

With a nice metal case like that, industrial strength construction – it’ll last forever! Of course, this thing will never leave my desk, so the ability to be run over by a truck is more or less academic.

So with my natural preference for hard core engineering I’d like to report that the best software comes from a group of driven software engineers. Technically, that may be true – a big group of engineers can make a very technically sophisticated product. But, really great products? Well, that requires a lot more than just technical excellence.

I think this is the backstory behind Vista’s successes and failures. We’ve been using Vista is our corporate OS since January of 2008, not long after it was widely available. It’s worked very well for us – even better since SP1. But again, we’re engineers: half of our systems are 64 bit, and we use high end hardware so we were very good candidates.

A Whole Lotta Polish

Last weekend I installed Windows 7. Now, even though I generally love new toys I haven’t been chomping at the bit to try out Windows 7 because Vista is working great for me, and we’ve had a lot of deadlines I didn’t want to risk. But, with the release of build 7100 last week, I couldn’t resist.

What’s the big difference between Windows 7 and Windows Vista? Polish. A whole lotta non-engineering polish. I was using the media center capabilities last night and noticing all of the little things that are completely irrelevant from an engineering / functional standpoint. These same things make all the difference in how you perceive the quality of the product and, more importantly the quality of the experience in using the product.

Is Build 7100 without issues? No – there are some optimization issues that I’ve run into, but they’re likely known already within Microsoft and they have months to refine them. The big picture is that the risky, time consuming design details are all there. I haven’t even turned off UAC yet, and I couldn’t live with that under Vista for more than two hours.

Now, it may be that if you’re creating the next version of SQL Server that this fundamentally human element of intuitive adjustment and polish isn’t as necessary. SQL Server could be all about hard core specifications, tests, and optimization. That’s reasonable when the human to product interface is either through a standard you can’t affect (e.g. T-SQL) or is confined to highly technical specialists.

Goes to Eleven

When you’re creating an application, you aren’t going to find the polish by reading a functional specification. You also aren’t going to get it just by using any particular development methodology – Agile, Waterfall, whatever. What you have to be willing to do is go beyond the written functional and system specification and look carefully at each aspect of the human – computer interface in your product.

This dedication requires a few things:

1. Access to a User Experience (UX) / Human Computer Interface (HCI) specialist. These folks are experts not for facts and figures or things you can read in a book but their experience and practiced eye that lets them pick out the key details that make all the difference.
2. Dedication to making it better: At each turn, and in very difficult moments, you’re going to have to repeatedly look at what you have and what you’ve done and say OK, how do we make this better. Take the case that we can leap beyond this, what would that look like?

Done right, this experience can be tortuous to engineers because it’s about iterating through hard to quantify, experimentally determined states without objective metrics to guide your process. You will see the results of your work – but as the sound of distant thunder as your users either rave more and more for what you’ve done or just accept meekly what you give them. Engineers are used to tweaking a knob and seeing the needle move in a quick, quantifiable way.

If you want to get a sense of what happens when people think deeply about how to create software that interacts well with people, read the Microsoft document on how to write an error dialog for Vista. This is 28 pages on how to do a good error message and why. Warnings? another 12 pages. Even if you’re a hard core engineer, some of the Vista User Experience Guidelines is a great read to understand why it takes many iterations and at least equal measure of instinct and intellect.

Fighting the Good Fight

The challenge with pushing for breakthroughs in the user experience with your product is that it doesn’t fit well into traditional engineering problem solving techniques. That may be why some of the most successful organizations at it have a strong command & control personality (like Apple) that emphasizing an individual making an intuitive judgment to decide what’s best. Trying to apply traditional engineering approaches will generally stifle and drive away the very talent that excels at solving these problems. Just ask Google. Their well respected expert on design and usability quit this year, saying:

I’m thankful for the opportunity I had to work at Google. I learned more than I thought I would…. But I won’t miss a design philosophy that lives or dies strictly by the sword of data.

The full text is an interesting read. Probably the most poignant example was testing what shade of blue should be used in a specific scenario. This is a good example of trusting your judgment, but don’t try to explain it. It’s a fundamentally human, intuitive leap and you might be able to rationalize it, but that doesn’t mean you can really explain it.

The best part is that if Microsoft is finally getting the message that it isn’t enough to just complete on business and engineering requirements but instead you have to battle for the hearts and minds of the people that use products it’s only good for everyone. Just like Linux has pushed Microsoft to be faster at evolving Windows (and creating more low cost licensing options), this may push players that are known for great design to have to up their game as well. I can’t wait.

Everyone likes to be on the winning team.  We love to root for our favorite sports team, we like the car we own and the brand behind it.  So it’s no surprise that when Apple ran their I’m a Mac ads that Windows fans were in an uproar.  Now with the Laptop Hunter series the shoe’s on the other foot.   Microsoft is making a big show that Apple computers are overly expensive just for the Apple brand.  Apple fans claim that  to match a Mac, a PC has to be equipped with tons of antivirus software, a full time tech support guy, and a Witchdoctor on standby to keep it working.

Seriously people

First, Apple makes some of the finest hardware you can possibly buy.  If you compare it nose to nose with hardware that’s actually built to the same standards then it really doesn’t represent a significant price premium.  Compare a Macintosh Pro with an equivalent Dell workstation – the cost is within 5%.  It’s amazing that Apple can afford the extra engineering of an OS with that little premium.  

Second, Vista works great.   It’s running on many more systems than Mac OS is, and with volume comes a range of new problems.  The total amount of money I’ve spent on desktop antivirus software in 10 years of administering PCs?  $0.  The total number of virus problems I’ve had? 0.  My parents managed to get into trouble with one virus and Windows XP – but installing the (free) Microsoft Defender cleared it right up never to return.

As with nearly all marketing, this is a battle of perception:  Apple has done a great job of defending their brand at every turn.  This is part of their corporate ethos.  Along with a few other tenants it ensures they are a much loved but niche player:

• Only do something you can do uniquely well.
• Don’t extend into markets that might ask you to compromise your values.
• Cultivate the mystique:  Don’t show what’s behind the curtains.

Microsoft on the other hand has tenants that ensure they’ll be a volume player, but an unloved one:

• Play to win the most market share in any market you can.
• Build your ecosystem by making it easy for others to add value to it.
• Cultivate the engineers:  Provide overwhelming amounts of documentation and approaches.

The fact is, many people don’t need a top end piece of hardware like a Mac.  On the other hand, many people want a computer that’s just a tool, not a piece of art.  To them, the nearly infinite diversity and low cost of entry are essential.

I’m a People person.  I’m Good with People!

The computing needs of the average corporation and the average individual are very far apart.  To companies, computers are tools – like the desk, phone, and copier.  Very important, very powerful – tools.  They aren’t there to make you feel great or enable you to create a cool video of your vacation in France.  My partner really summed it up one day when he commented that the Mac was a really personal computer - it worked hard to create a personal connection.  

Corporations on the other hand want slow paced evolution, massive support for legacy applications and hardware (these guys are still running dot matrix printers off parallel ports) and to control costs.  They also philosophically want to have all the keys to the computers – just like they do for the buildings and offices they own.  PC’s are just end points on the large mesh that is the corporate IT network.  It’s very impersonal.

Microsoft makes a great deal of money providing businesses with the tools they need to have the computers work for them, and Apple makes a great deal of money creating computers that people love.  Either of these goals would be compromised by trying to do both.

Vista Goggles

Folks that have been in the Windows ecosystem a long time probably recognize that you could take the first year of press about Vista and substitute “Windows 2000″ and find the same article written 8 years earlier.  Vista is a surprisingly large and tricky step forwards on a number of fronts, whereas Windows XP was a visual redress of Windows 2000.  

Almost like an SAT test:

Windows 7 is to Windows Vista as

Windows XP is to Windows 2000.  

Like Windows XP, the story on Windows 7 is making virtually no architecture changes and instead just tuning for the long haul.  That’s a great thing, because there’s a lot that works very well with Vista, and now it’ll work even better with Windows 7.

The humorous thing is to read now about how people are thinking about moving to Vista once 7 ships because, well, they don’t want to move to an OS that was just released.  It’s as if Vista has been aging like a fine cheese on the shelf so the very same binary code that once was toxic is now just what the doctor ordered.  To a slight degree this is true:  Vista SP1 did address some issues that affected some people, and more importantly hardware now is dramatically faster than it was two years ago (as it will be two years from now…) so what once was aggressive is now commonplace.  The same was true of Windows 2000 when it shipped.  Requiring 64MB of RAM?  That’s just crazy talk!  Only certain video cards worked reasonably with it, and video drivers to a while to stabilize.  That sounds very familiar…

In the end, it really comes back to Perception.  Probably the biggest mistake Microsoft did was not push the OEM’s that make the computers to build machines that could responsibly run the new operating system, and be clear that meant hardware 3D video cards and plenty of memory.  And oh yeah, stop putting aftermarket firewalls, antivirus, Google Desktop, and all kinds of other things on them that are ill optimized.  At my last company we got in the habit of routinely wiping each new Dell that came in and reinstalling the OS from the Dell restore CD – because that got rid of all the noise.  It was surprising how much better that worked.  Is that Microsoft’s fault?  Not directly, but they certainly could have found a way to encourage the ecosystem to forgo some profit for usability.  But that’s just not in their corporate DNA.

With any luck, the big story for Windows 7 will be that Microsoft pushes back against their channel, even being willing to risk it by leaving Windows XP out there for folks that don’t want to play by the Windows 7 rules.  It’s hard to put up barriers when you’re a legal monopoly, so find ways to use incentives to do it right instead of punishment for doing it wrong.  And keep up the ads, because perception does matter in the long run.

Who knows, it may push Apple to get better too.  Just once when my iPod updates itself to enhance stability and performance I’d love to know what exactly was unstable or slow…

Since leaving my last company and getting into the wild as a consultant, I’ve been amazed by the divergence between the conventional wisdom prevailing on the Internet and what I see actually happening on the ground with clients.

The prevailing wisdom appears to be:

• Google is the world’s best technology company.  Anything they solve they are the best at, and if you aren’t doing it their way you’re a dinosaur.
• Client / Server is dead.  All new applications will be web applications, most likely delivered as a service.

We visit a lot of companies, both prospects and clients.  Here’s what we’ve actually seen over the past two years:

• Outside of search, Google doesn’t have their act together.  Pretty much everything else is an academic experiment.  There’s nothing wrong with experiments, but there’s a big distance from there to running your business.
• Business are run on Client / Server.  They’re still creating new apps this way – they may use newer technologies like WPF to do it, but if it is core to making the business work, it’s usually not a web app.

With a name like Google, it’s got to be good!

Our own internal experience mirrors this.  We use Exchange and Outlook for email so I can’t say a lot directly about Gmail, however it’s clear from Google’s reactions to recent outages that their perspective doesn’t fit the enterprise because it doesn’t take into account the premium companies place on predictability and communication.  Predictability meaning that things are consistent – you get a consistent experience so your users can get their jobs done.  Businesses are change averse for good reason:  Users will adapt even to crazy problems and discover the patterns that work to get their jobs done.  When the patterns keep changing, they get frustrated.  On the communication front, businesses prize feedback on knowing the true scope of a problem and how long it may take to get it resolved.  

SalesForce learned this a few years ago and in response introduced Trust.Salesforce.Com, which went a long way to getting companies what they wanted to be comfortable with an outsourced critical solution.   If you operate a SaaS, you would do well to model after this.   Now, it isn’t necessarily bad that Google doesn’t do anything like this for Gmail – it just means it isn’t a solution for a large set of businesses.  

The thing we use the most internally from Google is Google Analytics.  It’s very pretty and easy to use, however we’ve noticed a lot of “what’s broken today?” experiences with it, enough that we can’t recommend it to anyone.  Two of the sites we monitor appear to be chronically under counted by Google Analytics, and we can’t figure out why.  And like most things Google – you’re on self support.  Now, there are paid options however unlike email we haven’t been able to find a strong paid competitor that is actively competing with Google.  It feels like most have left the field of battle, or are exorbitantly expensive (and aimed at large enterprises).

After much early on talk about how Google Docs was going to make Office obsolete, it simply hasn’t come to pass – and Microsoft continues to sell a lot of copies of Office.  It turns out that making a great word processor and spreadsheet is a very hard problem to do through the web.  Now, you might take the perspective that Microsoft’s announcement that they are going to offer lightweight web versions of Office 14 applications as being an admission that the old model is bankrupt, but it really points to an increase in reach:  Reaching many users that wouldn’t have been purchasing the product before.  Casual home users that wouldn’t purchase a “real” copy of office may find what they want in Google Docs, and would also be happy with a lightweight feature set of Office.

In Google’s defense, the products are worth what you’re paying for them:  Free.  But, you have to ask yourself:  If it wasn’t for the Google brand, would you give them the time of day?  For search, absolutely.  Finding an address and getting a street view?  Bring it on.  But don’t feel bad for depending on traditional software next time you want to buy a copy of Office, Photoshop, or use Outlook for your email.

It’s all SaaS These Days

Make no mistake, web applications, SaaS and Cloud Computing are all here to stay.  However, that doesn’t mean that there isn’t a lot going on in Client \ Server as well.  The key question to consider is how many applications you would have made, but done in another technology are being built as a web app instead?  There certainly are some, but for the most part web applications are creating entirely new spaces and solving problems that weren’t being solved before instead of replacing entrenched problems.  

Take document management:  On the surface this feels like a problem that should go entirely web and not look back because the web is very good when the readers to editors ratio is very high.  That said, the big document management companies still have very robust, integrated traditional offerings as well as their web portals.  You do have people using web document management solutions (like SharePoint) that never had document management before, which is a case of expanding the size of the market not replacing an alternative option.

When you are running your business, you have a set of requirements that are often best suited by a traditional client application:

• Users need advanced capabilities:  Once you stray out of the basics, it is invariably harder to provide features through web technologies than traditional technologies.  Tools are improving and making it better, but the cost per feature is lower in a modern client development environment than through a browser.  This is particularly true since you can put a browser in your app to enable things that it does really well – like show HTML content – you just let it do and keep the tricky stuff – like that big set of coordinated data entry fields – in your traditional app.
• Users are doing a lot:  One thing that is easy to lose perspective on is that when you run a client/server application every computer is bringing power to the party.  You often don’t need that strong a central server because the real action is happening out on the clients, and every new client that logs in is bringing their own muscle with them.  In the web, it’s all on the server. Not only that, but you’re rendering things in a less efficient way due to the stateless nature and limited protocols available for data exchange.
• Users need access to diverse data:  With web technologies it’s straightforward to manage information once you’ve brought it into the cloud, but it’s tricky to provide end users with fast casual access to a range of data in a range of formats.  In many businesses data is coming in pieces from many sources and being assembled to produce a coherent output.  This isn’t easy to do in any environment, and it’s one thing that the modern PC operating system, particularly Windows, has gotten very good at.  You can double click a file and almost always get it to open into a good viewer.  You can preview files, drag and drop from one program into another or a file into a program.  All of this is intuitive and fast for users that aren’t fitting into a pre-packaged user scenario.  

There are counter balancing effects:

• Transient user community:  The more far flung your people are, the more work it is to keep them up to date.  The more transient that user community is, the higher a barrier installation is.  This is the leading reason why you want to make something a web app:  It just isn’t worth the deployment effort to do it any other way.
• Diverse user community:  If you want to service Linux, Windows, and the Mac then web technologies are the lowest common denominator, it’s just the way it is.

What we’re seeing in the field fits into this:  People are creating a lot of new, lightweight web apps to solve point problems they probably wouldn’t have solved through technology before.  But they’re also still heavily investing in traditional applications.  

As a development team, it’s easy to get caught up thinking that Effort is the same as Value – just because something was a lot of work it must have a commensurate value.  The fact is, that there’s just no evidence that effort and value are correlated.  On the web, if you want to create a great looking and functioning generalized tool you’re signing up for a lot of effort.  And the value may be there – it could be that you’re going to reach a whole set of new users that otherwise wouldn’t use an application at all.  On the other hand, it could be that users perceive no extra value for it being in the web so all the extra work you put into creating the graphics, testing in five browsers, establishing identity, and the dozen other things you wouldn’t have needed to worry about if you were just running on the desktop netted you nothing.

So if you’re a business wondering how to approach that next application you need, don’t be afraid to get one that isn’t all wrapped up in Web 2.0 goodness.  In the end, it’s all about making the solution work for you and your users.

As you can tell from the timeline It’s been a while since I’ve posted anything.  It isn’t because I’ve had nothing to say – instead, I’ve been completely consumed by leading the team creating Gibraltar, a new application monitoring product for .NET teams that we’re launching.  You can download the latest version at  www.GibraltarSoftware.com.  We just published the last beta version of the product before the commercial release which is scheduled for June 1, 2009.

Bring a new product to market is really hard.  I’m sure you’ve heard that before – but however hard you think it is, it’s harder than that.  While we’re not quite across the finish line, there are a few things that have become readily apparent:

• Commercial-grade quality takes a lot to achieve.  At each turn where you might normally say “well, users just shouldn’t do that” you can’t.  Things you otherwise solved through training you can’t.  It’s the difference in construction of a commercial Amp and the receiver you bought at Best Buy.  
• Users won’t read anything.  We did a beta release where we posted in five places instructions for how to upgrade from the prior beta which required an extra step or things wouldn’t work.  We got deluged with calls about it not working from virtually every beta user; no one read any of the notes they saw, even in bold text in a yellow box in the middle of the screen.
• Marketing involvement early and often:  The feedback from our first beta version was brutal; it told us that we were going in entirely the wrong direction because the users we were building the app for weren’t going to buy anything regardless of how singing & dancing it was.  We had to step back and go a whole different direction.  That would have been far more painful if we hadn’t been early in the process.

From here on out, I’ll be contributing to a separate blog articles that are focused on .NET software development and being part of a small Independent Software Vendor (ISV).  This site will focus in more on its original goal:  IT and business strategies for reliable systems.

Many if not most software project leaders came up through the development ranks.  It’s generally thought of as a distinct advantage – you know the technologies you’re using, you can form your own well reasoned opinions about how hard something is, what is possible, and how long it should take.  For a long time, I felt that the best way to get results from development teams was to use my experience and knowledge to be very understanding of the challenges they faced and give them whatever time they asked for.  However, in the last few years I’ve run into several situations where I just couldn’t get them the extra time or relief from the most problematic requirements.  I predicted doom to the projects in question but instead I observed some of the best outcomes I’d ever experienced.

While the projects were successful, it bothered me that the secret sauce seemed to be a rigid adherence to schedule and delivery more than any other consideration.  This was exactly the reverse of how I wanted projects to succeed:  I wanted them to succeed because I was treating the developers how they always wanted to be, not like a stereotype from Office Space.  How could it be that better results came from ignorance of the technical details involved?

Developers Will Use All Available Time

Upon reflection, the first thing that struck me was how much an immobile deadline focused discussions and decision making. If you give a team more time, they will expand their process to consume it.  Time will get consumed by:

• Elaborate Decision Making: When you have little time, you make a choice and go with it until it appears it just can’t work.  When you have a lot of time, you sit back and look for the very best option.  That then requires defining what the best is – is it fastest, or smallest, or most scalable, or whatever.
• Development Approach: Under pressure you’ll tend to go with the proven guaranteed approach.  If you have the luxury of time you’re more likely to engage in yak shaving like investigating a new tool or approach, or writing several prototypes first before you develop the real solution.  You might even just throw caution to the wind by skipping a formal design figuring you’ll have the time to just code and test your way to a solution.

The more time a development team has, the harder it is to argue against spending it on up front luxuries.  It also can be harder to argue for long term best practices because the team has the time now to develop a solution any way they want.

Unknowns Create Boomerang Estimates

Even very experienced developers are generally terrible at estimating the duration of developing a solution.  This has been demonstrated over and over by many other parties.  The key behavior that we’ve observed is the phenomenon that from when you approach a specific development problem (like displaying a graph on a web page) until you know exactly how you’re going to solve it (and have a reason for confidence in that approach) you will tend to estimate high because in effect the only reasonable estimate is infinity.

Put another way, as long as you don’t know how you will solve a problem you don’t know for sure that it is solvable which means it will take an infinite amount of time to solve it.  Fortunately, developers are almost universally optimists so they believe they can solve anything eventually – so they’ll pull out a standard answer like three weeks or months or whatever feels like a big chunk of time to figure out the problem but not so big that it kills the project.   The reality is that until you know how you’re going to solve it, it feels like it could take forever.

Once a solution has presented itself  the development team will often find that all it will take is some cleanup and polish to be done- a very small amount of time.  What will push the team to find the answer?  We’re back to the problem of elaborate decision making when you have the luxury of time.  Finding solutions tends to not be a linear problem that will be solved with incremental development energy.  Instead, it tends to be solved by getting people together and brainstorming possible solutions until you find a few candidates and can work out what it’ll take to prove them out.  Under pressure, people tend to focus their creative energy and be more willing to compromise.   That flexibility will tend to get rid of pet requirements and developer gold-plating and focus on the most critical aspects of the problem.

What’s the alternate approach?

The key is to not let your knowledge and experience as a developer lead you to buy into the stories the team creates around what’s reasonable to get done and how long it will take.  Instead, you have to stick with the project’s goals first then the facts of the project.  The project’s goals form the objective reality of what has to be accomplished for the project to survive:  Deliver this functionality by that date, keep these people informed, solve these problems without causing those problems.

When the team runs into a wall and needs more time, instead of buying into the story of needing a lot of time, set a specific and tight goal that keeps a solid amount of time pressure on the team to solve the issue and prevent the problems above from showing up.  Ideally, find a way to give out one or two day chunks to answer incremental questions if necessary to emphasize that time is precious and has to be invested carefully.  This is where you can leverage your experience in a way that a non-developer can’t:  The team knows they can’t snow you with tech details, and you can define a specific, measurable result that can be achieved in a short period of time that they can’t argue with.  Despite this, you are bound to have to assert a few times that the time limit is the limit – solve the problem in that time.  It’s very hard because you’ve been on the other side of that conversation and it can feel like you’re the Pointy Haired Boss, but it’s fundamentally your job on the project.

What will nearly always happen is the team will surprise itself – a solution will be presented within the team that they can live with and can be done in the time they have.  It may be incomplete or have some risky shortcomings, and you’ll want to ask how long it’d take to address those.  You probably shouldn’t address them in the first round, but the team will feel better that you’ve considered through things and will buy into the outcome more if you ask.  You’ll also want to make a record of it so that the team can in the future recognize what was a predicted shortcoming vs. an accidental defect.

Do you want it solved right?

This is a question that often gets voiced within a team as a rebuttal to external time pressures and is very dangerous.  The challenge is that most non-technical people don’t get the number of ways that a problem can be solved: instead, each problem appears to have a single solution.  Take away your technical knowledge and imagine you’re the paying customer:  What’s the alternative – were you going to solve it wrong? If that’s the case, what else have you done that’s garbage?  If you took your car to a repair person and they said it’d be $500 to fix it, then when you came back they said well, if you want it fixed right it’ll actually be $1200, wouldn’t you wonder what the hell the $500 fix was?

Usually this statement is uttered in desperation when a team believes they just need more time to figure out a problem.  Nobody wants a problem solved wrong.  Skip the hyperbole and get down to action:  break down the problem into small chunks of time that can be invested for a specific measurable result, and make sure the team gets that overage time is the most precious commodity.

Side Note: This is an advantage of SCRUM in practice.  If you’re following an Agile Development practice, particularly SCRUM, this fits right in:  Focus on making each sprint deliver the user stories it was supposed to even if you have to leave some special cases for a later sprint.  The daily stand up meetings are a great place for the different team members to apply team pressure against over engineering and doomsday estimates.

Cleaning Up and Closing Out

At some point you need to close out your release and ship it. For each of the areas where you’ve had to make compromises and taken shortcuts you have to choose to either:

• Ship as Final: Decide the implementation is close enough to the intent of the end-user functional requirements that it can be the final implementation (at least until new information contradicts this decision)
• Ship as Temporary: Decide that something is better than nothing and ship the feature with limitations.
• Cut the Feature: Hold back the feature until it can be reconsidered or reimplemented.

You’re nearly always better off shipping the feature, often as a final feature pending more information because it’s very hard to gauge the true impact of each limitation.  This is particularly true of user-facing features and environments where it’s possible to evolve the software rapidly.  Inevitably once it’s in the hands of your users you’ll discover aspects of it that you didn’t think of that will require rework and you may discover that the killer feature you were sure would be the hit of the release is hardly used.  In either of these cases if you’ve invested a great deal of time in making it foolproof the team will tend to resist changing it.  It’s a natural product of the presumed relationship between effort and value.  If necessary, you might put in some temporary safeties to detect and catch the limitations you’re worried about.

The major exceptions to this approach are areas that are too dangerous to deploy if less than fully trustworthy.  For example, if your team is developing a data storage system, software deployment system, or other critical infrastructure your choices likely resolve down to making it as right as possible or holding the feature until it can be reworked.

If it turns out that the solutions that are viable within the schedule have significant limitations, you should make sure these caveats are known to the business – provided you can express them in business terms.  For example, knowing that an algorithm won’t work if your userbase doubles is probably not a significant caveat, unless you know the business plans to double in a relatively short period of time.  Every system has limits, and every software change has risks.  Business representatives don’t like to hear the same items covering the same ground repeated every time you discuss software, and it tends to make them not hear the new and important information as well as sound like you’re attempting to transfer accountability from your team to them.