Then there is Rick Welch's approach, which is to shoot only one arrow, go and pull it out of the target, and then shoot it again from someplace else, never shooting it twice in a row from the same spot. He violates this rule occasionally if you clearly blow a shot, when he will sometimes go and get the arrow for you and ask you to shoot it again from the same spot. He doesn't require perfect form for each shot, just generally as good a form as a student is capable of at that time. This means that a certain amount of targets are missed, which is okay as long as the student is generally applying the information Rick has given him. This is different from an obvious error like a pluck or a peak or a dropped bow arm, which will generally result in another shot from the same spot.
Not to take away from the methods being described above, they are fine and time-tested methods. Just that there is more than one way to skin a cat, and some people react better to different teaching methods.