Giving a bad teacher more money won't make them a better teacher. Maybe you can argue that offering more money to teachers will draw in qualified people from other professions, but this kind of solution can't be implemented in a vacuum. The bad teachers are already in the schools and cannot easily be fired because they're protected by politically powerful unions and furthermore, protected by a substantial portion of the public who hold school teachers on a pedestal and will resist any political move to make it easier to fire bad teachers.
