Teachers paid according to student to student academic results

Leaving teachers to be paid according to students results is pathetic, because academic results don't represent the hard work of the teachers. Students must have worked and studied their subjects for the exams; however, not everyone do what they must need to do, so for that reason the responsibility is one of the issues that results don't applied to the work of the teachers but of the students. The paid of the teachers must have depended of their way of teaching, but obviously the paid depends on the results of others and that is not fair.