One of the best definitions of happiness out there is this:
When you have found your "why" and you begin to think, talk, and live it, your life will become a living manifestation of your mission.
The really successful people and businesses are those that understand their story and have the ability to relay that story in a way that resonates with others. Your "why" can help others find their "why." The source of your happiness (id est, your art) can help others find their sources of happiness.