Police don't prevent crime, they're the cleanup crew.

Same with firemen. Frequently their job is to mainly prevent the fire from spreading to other buildings, not to save the involved structure.


Electronic techs: I can't fix a machine, I could be removed/retrained

Drill Sergeants: Their Privates don't make the grade, they can be returned to their original units with their careers ended.

Instructors (In most of industry outside of a school system): The students don't learn the subject matter, they lose their job.

Managers: The function they are responsible for doesn't perform, they're on the street.