The motivations of adults are, usually, not the same as those of younger people, so that some people may be more skeptical to respond, too. Obviously, I'm generalizing here. But there are logical reasons behind that.
There's also that if you're 45 years old, people expect to see some accomplishments, and are skeptical if you don't have any, whereas there is no such bar for 12-year-olds other than perhaps curiosity and ambition.