Actually the conductor is just a guy that moves a stick. His job is to wake up people (especially in the audience) who fall asleep, either through vigorous movement of his stick, or, if all else fails, by sticking his stick in them.
He is usually the guy that was not good enough to play in the band, and never got picked. Or maybe he plays the accordeon, which doesn’t fit with a string orchestra. But he looks good in a frock, which is why they let him play with his stick instead.
Also, it is important not to be too tall or too fat, because you’ll be hiding the people on stage from the lady in the front row, who’s usually some rich bitch or a corrupt politician’s wife. And you don’t want to piss her off!