There's great research about zero defect software, and my favorite is a weird grey textbook by Capers Jones called "The Economics of Software Quality" In it yo

There's great research about zero defect software, and my favorite is a weird grey textbook by Capers Jones called "The Economics of Software Quality" In it you'll find that this level of requirements gathering, blueprint/spec writing and code inspection are actually cheaper in a relatively short time (months, not years). Writing specifications that are extremely detailed ends up giving you all the logical failures ahead of time, and makes typing code more of a spell checking exercise. By having the logical failures before the code ever runs, you get to debug & fix them before any code runs. This ends up being faster & cheaper in total than waiting for users to find bugs. However - I understand that for many companies they actually don't care if users find bugs as time to market is more expensive than the future bug finding. But if you have a product already in the market, and you expect to support it for ~year, you probably can do much more detailed design and avoid so much pain.