Here's what can be considered a funny/tongue-in-cheek excerpt from Manrique...
(About being a professional, with special attention to #9)
A Perfect Professional proceeds like this:
1- He never rushes to lose.
2- He never rushes to recover.
3- He never rushes to win.
4- He never rushes to leave.
5- You do not stay in the casino more than the time you need to win.
6- When you are losing, you play less or don't play, or stop playing.
7- When you win, you don't get excited or do calculations about how much you are going to win, you just think about what to do when you start losing.
8- Always, even if he loses, he leaves with something of what he brought.
9- Reads Manrique.
"Don't give me a system, give me a concept, my great mentor Nono Santelli always said."
―Manrique
"A professional will need to master much more than systems to win. What separates professionals from great professionals is not so much mastery of knowledge, but rather the criteria for executing that knowledge."
―Manrique