I've heard many canned responses to this, mostly about youngsters having more energy and in some way that extrapolates to having more "potential" or being better for a company. But my question here is, really?
How can age alone tell you about how well a person is going to perform or how valuable of an asset he can be to a company? After some thought, I agree it is one factor, but I still maintain doesn't entirely make a case for or against anyone. In fact, I feel it's kind of unfair to those over who are "less" preferred in startup jobs. If a person is willing to learn, has talent, and is passionate — heck, give him a shot.
I'm not accusing you of doing so, just pointing out a trend. And BTW, I'm 18 years old.
You obviously have more experience in hiring (maybe even firing) people, so could you tell me if I'm right here?