I have a friend who is a fantastic teacher.  He is bright, worked hard and cares for his students.  Unfortunately his Principal did not like him.  Long story short, he ended up being sent to a rubber room where he spent 5 months and then, without even being told what he was being charged with, all charges were dropped and he became an ATR.

Friend has worked in various schools.  In each, he strived to do his best.  He cared about the kids.  But a big red R was branded on his forehead and no matter how many kids he reached he was never good enough for the administration of the schools where he worked.

Friend is disillusioned and is retiring this year.  He's taken enough abuse to last multiple lifetimes and he has had enough.  He's still being abused by his Principal but he's Teflon now and has told the evil bastard to bring on the "U".  The newbies in the school have been told to stay away from him.  The only people in the school talking to him are custodians, school guards and cafeteria workers, the ones the Principal cannot control.  It doesn't bother him since these are the real people, the ones he connects to.

The school system is losing an experienced, caring educator, one who has made a difference and would be continuing to make a difference if the system permitted.  His school administration and the city are winning as they are getting rid of another senior teacher.   He is winning because he will be able to collect a nice pension for the rest of his life.  The kids are losing but no one really cares about them.  Schools are a business and kids don't show profits.