Ah, pot commitment. The closet maniac's excuse to get wild and reckless. Pot commitment, which refers to the pot odds for your present stack size compared to your odds of winning the hand, is a fairly basic concept in poker, but unfortunately, it's also one that is often used to justify bone-headed behaviour.
Assessing your actual pot commitment means rather than measuring the pot size in relation to the size of an opponent's wager, you are going to measure it against the remainder of your stack. As such, you are deemed 'pot committed' when your odds of winning the hand are greater than the pot odds for the rest of your stack.
Pot Commitment: An Example
Seem a little too abstract? Let's break it down with an easy example.
You and your opponent both begin with $500 stacks. By the turn, you have accumulated an $800 pot split evenly between you (so you both put in $400), leaving you each with $100 stacks.
Let's say you have a top pair. In this case, you are basically pot committed and it is not in your overall best interest to fold on the turn or river. This is because your pot odds relative to your remaining stack are 9:1. (900/100 - you need to account for your own stack to get the total pot size.)
With 9:1 pot odds, it is almost certain that you have a better chance of winning the hand, even if you are up against an aggressive opponent. Yes, it's true you may not win this particular hand, but in the overall scheme of things, you stand to win more often than you stand to lose. To justify the fold, you would need to be sure that your chances of winning the hand were less than 10% (the percentage equivalent of 9:1). You can learn more about pot odds and ratio to percentage conversion here.
The lesson? You should never shy away from acting if you are pot committed. You don't have to make crazy raises, but at least call. Your pot odds increase when you have more of your stack you have committed in the pot and as a result, the greater your pot commitment.
When Good Commitment Goes Bad: The Ugly Side of Pot Commitment
Just because you have put most of your stack in the pot DOES NOT mean you are pot committed. By definition, pot commitment involves accounting for your odds of actually winning as well. Tossing your last chip in the pot when you have zero chance of winning is not strategic; it's just stupid. If you don’t have a good enough hand, fold.