Musashi, in the book of five rings, explains that to him one of the most important principles of martial arts is to bring the mind back.
To bring the mind back is to bring your awareness back to the stage it were before any attack.
When you make your move you mustn't keep your attention on the action or the effects of it, you must bring your attention back to the big picture.
This perception is useful for sword fighting and for poker.
The flexibility to "reset" the mind after any winning hand is fundamental to a good poker player.
The understanding that any loss must come without additional pain is also very important in every-day life.