Sometimes, the instructor doesn't know.
I had one student whose circuits and landings were consistently ok, but not good. We'd completed all the emergencies - the "must do" things before first solo. One of the few things we hadn't done was short-field techniques. We briefed for short-field techniques, and went out to learn them.
First landing, we nominated a point to be the start of our "short" runway, and the student did an absolutely perfect landing - except he landed before the "start" of the runway. Not to worry - let's have another go. Same again. I now had a choice. Other than those aspects which are specific to short-field, everything the student did was up to solo standard. Do I carry on teaching short-field? Or do I turn the flight into a solo checkout? I decided to turn it into a solo checkout - threw in a couple of emergencies, and one or two "normal" landings. Landed, sent him solo, and carried on with short-field landings another day.
FFF
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