Why I Test the Same Thing Five Times

When you build software, the computer will happily tell you everything is fine while something is quietly broken. Learning not to believe it is most of the job.

Here is the trap. Code "compiles." Tests "pass." A little checkmark turns green. All of that means the same small thing: the machine could assemble the parts without choking. It says nothing about whether a real person, on a real phone, gets what you promised them.

I learned this the embarrassing way. Early on I "fixed" something and confirmed it by searching the finished code for the change. The change was right there. I moved on. The behavior was still broken one layer up, where the search could not see it. Then I found three more problems that all would have passed the same check, and were only caught by opening the actual app and using it like a stranger.

So now I test the same thing more than once, on purpose, in different ways:

Once in the code, to see the change is there.

Once in the real product, on the device people will actually use.

Once as a suspicious stranger, doing the clumsy things real people do.

Once at the edges, where I try to break it instead of prove it.

Once on the screen next door, because new work has a way of quietly breaking old work.

That sounds slow. It is slower than trusting the checkmark. It is a lot faster than shipping a broken thing to a real person and finding out from them.

The one-line version I say to myself: a passing build proves nothing about correctness. It proves the parts fit together. Whether the thing actually works is a separate question, and the only way to answer it is to go look.

This matters more now, not less, because more of us are building with an AI writing the code. The AI is confident by design. It will tell you it is done in the same cheerful tone whether it is done or not, because it cannot open your app and see the button do nothing. That check moved to you. It is now the most valuable ten minutes in your whole process.

Trust the build to be fast. Trust your own eyes to be right.

I write Building in the Open about designing and shipping a real product in public, one honest week at a time.

Curious how solid your own build-with-AI process is? Take the 4-minute check → aneilrazvi.com/maturity.html