And when you get too old / expensive / wise to the absurdity, they manage you out anyway. I've seen it happen in less than six weeks - informal support plan, threat of a formal one that will go on your record and a suggestion you go elsewhere. It's not happened to me yet, but it undoubtedly will.
I cannot stress enough to anybody not to go into teaching. It becomes a trap - you need the money and it is increasingly difficult to think of what else you could do for the same income.
Just as one example - everything at my school is currently focused on reducing detentions or removal from lesson. As long as week on week, the stats show this is happening, it does not matter what behaviour goes on in the actual classroom. The behaviour hasn't improved one iota, but the detentions have decreased because the staff are too afraid to set them, so SLT are stating this as a win.
I'm 25 years in and I don't actually hate it on a day to day basis, but it's taken so so much from my life and my mental health. I genuinely believe my life span has been shortened as a result of the constant stress.