Greg Esres wrote:
if they don't "know when to go"

Probably the instructor is at fault, sometimes, when they teach
students how to "save" landings. The student isn't always capable of
determining which should be saved, and which shouldn't. I know I
scared myself once or twice as a student pilot.

Well, there's a balance here. On the one hand, the student
does (IMO) need to be taught how to save a landing, because
something can go awry and the correct reaction needs to be
there. Just pushing in the throttle won't always do it.

OTOH, sometimes this is taught as almost a "normal" procedure,
rather than "when in doubt go around NOW". I think solo landings
should be like landings in a strong crosswind: plan to go around,
and if you find yourself over the runway correctly aligned at
the correct airspeed in the correct attitude, go ahead and land.

But that's just my opinion and I'm not a CFI.

Cheers,
Sydney