It's easy to point out the places where you could've done a bit more optimization after the fact. And, yes, sometimes those optimizations don't cost an arm and

It's easy to point out the places where you could've done a bit more optimization after the fact. And, yes, sometimes those optimizations don't cost an arm and a leg, but it's very easy to fall into the premature optimization mode that kills the product and the company. Not everybody has tons of funding in the bank. For some startups shipping a day later can put you in the death spiral trajectory. Timing is a huge factor in a startup success. It's easy to think why not just do it right in the first place. Aside from the timing you, as a startup, don't really know what "it" is or "it" is constantly moving. Committing to perfection at that stage can be a sure way to kill the company. Even if "it" is known and it's not changing you still need to keep in mind the Gall's Law.