I want(ed) to do a video about this but I never sat down and did it.
It came out of DCC RPG and the 0-level character "funnel." Each player gets 3-4 0-level characters and most of them are expected to die in the first 1-2 adventures, leaving only one character that gets to attain 1st level and pick a class.
One of the major design decisions in DCC RPG is the use of player intelligence and reasoning to figure out traps and puzzles instead of relying on dice rolls for adjudication.
The video would have compared two traps: the first is my classic 10-count crushing ceiling trap (where each time you press a button, the ceiling retracts to its original position and the count-down starts over from 10; the only way out of the trap is to not press the button and let the count down reach 0, at which time the ceiling stops a foot or two above the floor and a secret hatch lets you escape) and the second is the One Man Left Behind trap (a piston-mounted lever concealed inside a column that requires one PC to seal himself in the dungeon in order for the others to escape).
The point of the video was to contrast the two traps to reveal what each taught the players.
The 10-count trap is nice for a mind screw but it is counter-productive in the long run (and especially in a game like DCC RPG). In the short term (while they are trapped), the PCs will become experts in exhausting every last idea on how to escape. Unfortunately, they are all in vain, as the only way out is to do nothing. This teaches players that anything they do is pointless. It also teaches them that the DM will not kill them and they should just trust him and let him direct the story without any interference. Bad bad bad. But fun for the DM.
The OMLB trap can have any number of details (i.e. exactly what is going to kill everyone unless someone holds down the lever) but its actual purpose is to allow roleplaying and, in particular, for the emergence of a true hero. Say the 0-level party has worked its way through the funnel, whittled far down in numbers, and vanquished the evil high priest in the last room. They then find the column at the beginning of a long hallway with a door at the other end. Inside the column is a handle attached to a cylindrical weight that just fits inside the column. When someone twists the handle and lifts, the door at the other end opens. As soon as the handle is released, however, the door slams shut. So, one PC must remain trapped in the dungeon in order for the others to escape.
Watching a party decide which guy stays can be entertaining and enlightening, especially since these are the PCs who survived the rest of the funnel and, if players utilized the "send in the red shirts" method of play, presumably the 'best' characters by roll or race. It can end pretty anticlimactically if one players has multiple PCs remaining while the rest have one each, or if one of the PCs is a really crappy roll. But the trap works well with the 0-levels because no one's favorite character moulded over months of play has to die somewhat arbitrarily (and no one has much equipment available to jerry-rig an alternate way of holding the door open).