Re: 14, a pivotal age in shaping our musical tastes?
I'd say your teen years in general are what shape your music tastes for the rest of your life (but 14 is probably a pivotal turning point).
It was 1989 for me and that would be around the time I stated listening to metal (particularly thrash) and that was it for me.
Having said that I have heard of many guys simply "growing out of it" and forsaking metal once they'd "matured"- weirdo's!!