Sometimes it's a character you want to play or a story you want to tell. Sometimes it's just to pay the bills.
All good is hard. All evil is easy. Dying, losing, cheating, and mediocrity is easy. Stay away from easy.
I don't set goals. Like, that's what I want to be doing however many years from now. I do what I love to do at the moment. If I wake up tomorrow and decide I want to dance, that's what I'd do. Or design clothes.