I disagree. I think working at a large company for long periods of time can actually stifle your ability to be a great founder. You learn bad habits and your intuition can be deformed by things which help you become successful at Big Co but are useless in early stage companies.

Also, I'm at Google and I know John and his work really well. It's almost laughable to imply it was involuntary. John is an all star. The guy actually wants to do a startup because he find the challenge interesting.