this thread seems to be entirely based in a "rock" perspective - what about jazz musicians? Blues musicians? Pop / Rock is a relatively new musical genre - it's less than 50 years so it's only hitting middle age as a musical form. The afore mentioned genres have been around 80 years plus so a lot of musicians are, obviously, older - rock music will go the same way, bands such as the Stones, Neil Young, etc is will be the norm rather than the exception. Longevity will be based on talent rather marketing. I find it sad that someone sees fit to give up at 23 - this is purely based on his narrow world view of what music conforms to but that view will change in time after he's exposed to more musical forms & genres and, basically, hears more music over time. Music isn't like football - age doesn't diminish talent. However, rock music has always been marketed as a "teenage" or "youthful" genre - again, that perception will diminish over time. As long as you enjoy music, play music.