Some people have listed "what ifs" or "if only" in his/her respective debriefs (see my sig for mine, but I don't really have any "if only").
bb has linked you to the quote thread. Outside of those two, it's probably one offs here and there.
Strategy Discussion Thread | Strategy Master | GMAT Debrief| Please discuss strategies in discussion thread. Master thread will be updated accordingly. | GC Member Write Ups
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