One of the wonderful things about acting is that you can also work when you're 75. It's an interesting career: it's never totally on, but it's never totally off, and I will always work until it doesn't interest me.
I never quit until I get it right. I've been that way with everything I've done. Sometimes that probably keeps me from enjoying things at the moment, but it is also behind whatever success I've had.
Acting's a lot of fun when you don't treat it as serious business.