It's really about...corporal punishment!
Every once in a while, I hear someone (usually over the age 60,) talking/joking about how when THEY were growing up, their teachers (nuns, usually,) would smack them for getting an answer wrong. Usually the story involves making the point that, however cruel and uncivilized this appears now, it actually *worked*, since the student never forgot that particular answer ever again! (and was even better at learning other answers for fear of the lash.)
now, of course I would NEVER do this, but everyone once in a while... I really want to smack a student. Only because I think that it is something like THAT which will make her (usually) recall the answer to a particular question, or at the very least, never forget it again!
A couple times recently I've had situations like this:
"(insert name of child,) what is this note/other musical question?"
(long period of waiting...)
(I attempt to be extremely patient, offering helpful hints, re-explaining things in different ways, trying to guide the thought process)
finally I say,
"this is a g/we call this a quarter note/whatever the answer is..."
recently, it happened that the student needed to know and could not remember the EXACT SAME answer to the same question a few minutes later, after ALL of that explaining... and that got me thinking of how the answer would probably not have been forgotten so easily after having been explained, had I had some instrument of corporal punishment handy!