Brad Gilbert, in his book, Winning Ugly: Mental Warfare in Tennis - Lessons from a Master, says:
“...when you get down on yourself—start beating yourself up mentally—there are now two players on the court trying to take you down. And one of them is you.”
He talks about how Serena Williams and Venus Williams are examples of players who have short-term memory loss in a good way. They quickly wipe the slate clean and get on with the business of winning.
What a great lesson for business also! Robert Hollis says that limiting beliefs come when we hold on to the pains of the past!