Daniel Pink wrote a great book about this called &quot;Drive: The Surprising Truth About What Motivates Us&quot;. Review: <a href="http:&#x2F;&#x2F;www.entrepreneur.com&#x2F;article&#x2F;218852" rel="nofollow">http:&#x2F;&#x2F;www.entrepreneur.com&#x2F;article&#x2F;218852</a>