How do great leaders inspire action?

Why are most messages so uninspiring, so unconvincing?

By the same token, what magic do both the speeches of Martin Luther King and the marketing of Apple have that move us to believe and act?

Simon Sinek, author of Start with Why: How Great Leaders Inspire Everyone to Take Action, has an interesting theory:

People don’t buy what you do. They buy why you do it… Start with “Why.”

Check out his interesting (and inspiring) TED talk: