In response to "Teachers Quit Principals, Not Schools," in which the author argued that teachers leave because of poor leadership, I would say the following: I'm absolutely certain that this is absolutely true in some cases, but sweeping generalizations that encompass an argument that all teachers leave schools for a single reason oversimplifies the issue. Schools are cultural fits, and it can take several tries to find a school with a culture that matches an individual teacher, which is why it's a bit sad when young, inexperienced teachers believe that because they didn't like teaching at one particular school, they don't like the profession, period.
If you're an older first-time teacher, one who has worked in other fields or industries prior to teaching, or you've taught at different schools, you may understand the distinction. You come to realize that because one job was terrible doesn't mean that all jobs are terrible. That professional experience, whether gained from teaching or simply from having worked at multiple jobs, is invaluable in making that distinction. Teachers ostensibly incorporate self-reflection into our teaching, teaching students how to reflect on their learning, and needing to reflect on our own teaching methods; yet teachers can be just as bad at reflecting on an experience and admitting hard truths to themselves.
Sometimes a school just isn't a good fit. Sometimes the administration is not good (one school at which I've taught had unethical administrators who passed failing students without consulting the teachers); sometimes teachers don't agree with how administrators lead and direct the school; sometimes teachers act unprofessionally and don't fulfill the terms of a contract; sometimes teachers just aren't very good at their jobs; sometimes there's not even any one particular thing wrong, or there's not anything even "wrong" as such - it's a matter of personality and fit. And sometimes teachers leave teaching altogether for better-paying pastures, or their professional interests change, or various other reasons have less to do with education and more to do with external factors. It's an oversimplification to imply that all teachers "quit principals." Teachers quit teaching, not necessarily people.