if they have real talent then they could have a fantastic glittering olympic style future...
if they are top end of average or bottom end of seriously good (far more likely)then they could have some fun - eg competing at county level, but they could also end up frustrated, disappointed, bitter - or worse (drug addled, no other career prospects, no idea of the real world)
And if you/they want to take it to a serious level then you have to push don;t you? What makes kids or their parents go for stuff like this? and is it a Good Thing? an entirely geniune question I have often pondered...