people don't buy what you do;they buy why you do it
Why do some companies achieve things that completely exceed our expectations and defy all of our assumptions for what's possible?
As Sinek points out, every organization in the world knows "what" they do. Many know "how" they do it differently, whether they call it a USP, a value proposition, or a point of difference. But surprisingly few really know why they do what they do. And the why is not about making a profit -- because that's the result of the "what" -- but rather their purpose, their belief, the thing that makes their employees get out of bed in the morning or their customers care.
"People don't buy what you do, they buy why you do it. And what you do serves as the proof of what you believe.