Many years ago (aged 17), I was sent off to do some practice circuits various including short field landings, in a C150.
The flap switch had to be held down from centre to lower flaps and from DOWN it was spring loaded back to centre. If it was moved from centre to the UP position would hold it there, so the flaps would fully retract.
On short finals, at low IAS I selected FULL flap, checked they were fully down (what a strange place for the indicator, well out of eyeline for short finals) then let go of the switch.
Unknown to me, the switch was worn out. Rather than the switch just going back to centre after letting it go from DOWN, the springloading overcame the centre detent and went straight to the UP position again.
I got a very strange sinking feeling.... I thought I had full flap but in fact the aircraft was becoming increasingly flapless.
Thankfully, I didn't bend it but it took a while to regain my composure. I taxied in totally confused about what had happened until I saw the flap switch was UP.