I think a lot of the startup failures of really early stage startups might be due to the entire team being exactly the same age and right out of college. So they make mistakes that have been made many times before. Put another way there are many mistakes that can kill you and the more experience you have on your team the better you are at identifying them-- but you have to have innovation and new ideas too.
Which is not to say that any of these sets of characteristics are exclusive to a specific age -- this is just generalizations.