Bang on the money MrMarketz.
I have no problem admitting that after all these years discipline of mind has been the hardest thing to achieve and to this day it is a constant battle. I talk not of motivation for hard work (no problem) but rather the fear that creeps in and doubt which begins to rise after a string of losses (all to be accepted as a part of trading). Yeh, only discipline, money management and pure belief in yourself will save you after that.
The 'Market Wizards' Books by Jack D Schwager are a must read and I'm glad you posted that since all os those whom wish to make trading a career ought study them. In life I think we can best learn from others mistakes and successes in order that we either avoid (mistakes) or emulate the greatness.
The quote in your post makes me smile - "In trading, you can't hide your failures. Your equity provides a daily reflection of your performance. The trader who tries to blame his losses on external events will never learn from his mistakes. For a trader, rationalization is a guaranteed road to ultimate failure.”
That particular quote probably applies to 95% of the 99% whom do not make it as traders. These are the ones whom I never see type the words at forums...."I failed as a trader because I was either lazy....undisciplined....didnt educate myself etc"....BUT rather blame every single loss on the "Broker whom stole their money" LMAO
In life, for as long as you can't say words like "I was wrong", "sorry" or "forgive me" etc which takes humility, there is no chance of self improvement as both a human being or truly excelling at what you do.
Pilot