The Tenth of these Principles is: Test.
It propels us forward, with Continuous Improvement.
It has no Ego, it believes only in data, Cause and Effect.
There is no Truth except what is revealed in the Results of our Actions.
The video clip at this link is a wonderful example of how continuous testing can create extra profits out of thin air, with the simple addition of a post-it note.
Roberto Monaco interviews Dr. Kevin Hogan who reveals an extraordinary discovery that increases response rates significantly. You will be amazed.
Highly recommended, for fun and profit!