Jorge Miranda, our high school principal, is a good poker player. I played with Hold Em with him a couple times and he ended up with the $$$. A key concept in poker is the "escalation of commitment" heuristic. In psychology, a heuristic is a simple, hard-wired rule, usually through evolution.
Bad players escalate their commitment with losing hands. Basically, once you put some money in the pot, you find it hard to get out. Even if your cards are telling you: "Fold." Emotionally, you tell yourself a story that your 7, 8, 10, J is still a good hand, because you feel like the 9 is coming. Or maybe you'll bluff to victory.
Your wishful thinking leads to bad decisions.
Does that happen in teaching?
I think so. It would be weird if this heuristic did not apply to teaching. It's part of being human.
That is, I think once you've taught for a few years, wow, it becomes hard to change. You've escalated your commitment. You've made some huge bets -- of your effort, sweat, and emotion.
To make big changes to your teaching style now would essentially be like "folding your current hand" -- and waiting for the next one. You have a very high emotional "sunk cost" in the current hand -- your current way of doing things. If feedback seems to suggest folding your hand, you question the feedback.