Someone asked me this question recently, and I was appalled that I didn't have a compelling, brief and articulate answer. Intent on getting my story right, I turned to Mr. Maslow for help.
We all want to sit at least three rungs up from the bottom of his Hierarchy. No point talking about my physiological, safety and belonging needs.
We all want the esteem of others. But bringing that up makes me sound needy. More than I already know I am, since being a performer carries some requirements for validation along with it by definition.
So it comes down to self-actualization, which is a toughie to talk about. How do you become self-actualized? Is it possible to achieve it through your work? Is it a state of mind, or is it a process? Are you born with it? Can you find it? And once found, can you lose it? If you get your ass kicked on the bottom four rungs, does it go away? Do you get there through struggle? Or is it natural?
I would think that the self-actualized make the best contributions to any endeavor. Kind of like happy cows give the sweetest milk. Ooo, maybe that's a bad analogy.
Ask yourself "what do I want to do" and see how far you get beyond "finish that presentation" or "get more sleep". Tricksy, isn't it.