How many plane crashes are prevented by pilots?
Any manually-flown landing would meet your requirements. If the pilot does nothing on final approach, the plane will almost certainly come to a fiery end.

Landings that were very, very close to a crash aren't reported all that often - if you made some monumental screwup and managed to salvage it, would you write it up for the FAA? Not many people report almost-car-accidents or red light violations either.