Being skeptical or looking at things with the downfalls in mind is very good. It does make our work and inventions better.
My wife whom works along side with me on some occaision always asks why are you doing it that way. some times it really annoys me and I get, well you know. Other times I stand back and look at it with others eyes and can see areas of improvements.
I like it.
however, my kids are grown, but that does not mean other's are.