Power
When you first kick off your career, you aren't going to have much power at all. Usually, as a dancer, you're part of an ensemble, which means you have to be a team player. You'll be under the thumb of the choreographer or director, and you'll need to basically do what you're told and do it well. If you try to pull a bunch of diva antics in your early career, you'll quickly get a reputation as a problem child and never be cast again.
Even though you won't have ultimate control, however, you will have power over yourself. You can control how hard you work, and how much you put into it. You have the power to always bring your A game, and that's nothing to sniff at.
If you become a superstar dancer, though, you might gain some power for real. Let's say you become the next start ballerina of the American Ballet Theatre, and the crowds are lining up outside to see your version of Swan Lake. When you're the one putting butts in seats, you'll have a ton more power than you did when you first started out. Just know that nothing lasts forever, and those younger dancers are just waiting to take you down.