While putting teachers in the same boat as waiters, programmers and CEOs does sound awful, I think children will still wind up being educated.
Remember, the goal here is not to ensure teachers are never incorrectly fired, it's to educate children. If a few teachers are incorrectly fired, but student performance goes up, that's a win.
This is what happens in many industries. For example, if a trader or hedge fund manager gets unlucky and the market moves against him, he can be fired. Unfair individually, maybe, but in aggregate the net result is that the traders who aren't fired tend to perform better.
Remember, the goal here is not to ensure teachers are never incorrectly fired, it's to educate children. If a few teachers are incorrectly fired, but student performance goes up, that's a win.
This is what happens in many industries. For example, if a trader or hedge fund manager gets unlucky and the market moves against him, he can be fired. Unfair individually, maybe, but in aggregate the net result is that the traders who aren't fired tend to perform better.