The Little Book of Market Wizards

Most traders would benefit by writing down each mistake, the implied lesson, and the intended change in the trading process. Such a trading log can be periodically reviewed for reinforcement. Trading mistakes cannot be avoided, but repeating the same mistakes can be, and doing so is often the difference between success and failure

as learning opportunities that can yield rapid improvement if handled well, you will be excited by them.
If you don’t mind being wrong on the way to being right, you will learn a lot.

Recognize that you will certainly make mistakes and have weaknesses; so will those around you and those who work for you. What matters is how you deal with them. If you treat mistakes

Recognize that mistakes are good if they result in learning.
Create a culture in which it is okay to fail but unacceptable not to identify, analyze, and learn from mistakes.