I know a poker player named Bob. Bob sometimes makes friends at the poker table, but he always makes enemies.
For whatever reason, every time Bob plays, he has to have an adversary. He'll pick out somebody at the table to be a villain. Maybe it will be because that player laid a bad beat on Bob, or didn't tip the dealer, or something even less related to the game. I once got to be Bob's enemy because I was wearing a blue shirt that Bob didn't like.
Having an enemy helps Bob's focus at the poker table, but it doesn't help Bob's play. He stops caring about his own chipstack and only cares about his enemy's. As long as that guy's stack is going down, Bob is happy, and he plays like it. Instead of using his chips to make money, he uses them to sabotage his enemy.
Since that's where Bob's focus is, and it's what he practices every session, Bob is much better at that part of the game he's playing than he is at the game everyone else is playing. He's generally very effective both at reducing the enemy's chipstack and reducing his own.
Fortunately it's pretty easy to take advantage of this if you've played with Bob and know what his motivations are. Even as the enemy, Bob's betting gets pretty readable, as long as you know that he isn't playing to win. But it's even better if you're at the table with Bob and an enemy who doesn't know about it, because both of their chips can flow steadily into your stack. I've stopped wearing that blue shirt to the cardroom.
Don't be Bob.
