Design, functionality, and test specifications are very important. But the process must be monitored and be very flexible. I'm not familiar with Google system,

Design, functionality, and test specifications are very important. But the process must be monitored and be very flexible. I'm not familiar with Google system, but in other big corporations the problem is that you end up with system which does not allow exceptions - so engineers end up requiring writing 10 different documents to make a small change which can be explain on one page and everybody will get it: support, testing, doc writers, etc. And these documents ended up begin written so that management is happy and not actual intended audience: tester, support, maintenance, documentation writers, etc. So these documents ended up being useless so .... The worst result is that engineers which do not write good code but write good essays end up with promotion and eventually destroying the entire product (not their fault - they just not talented programers).