First, it would mean a lot more to explain why you don't want to work somewhere if that company had actually offered you a job. Anyone can say that they don't

First, it would mean a lot more to explain why you don't want to work somewhere if that company had actually offered you a job. Anyone can say that they don't want to work at Google, but it doesn't have much force if it could just be a sour grapes rationalization. It would at least be good to disclose whether or not you've talked to them about it. Pretending that isn't a problem, though -- where does the claim that Google doesn't finish things come from? Google must have one of the highest ratios of number-of-devs-on-a-product to number-of-million-users-using-that-product in the industry! I see no reason to conclude that a Google engineer's work would be likely to be canceled and disused.