this is why you should never put the Italians in charge of installing safety speed governors on things powered by engines. They're like, "but why?"
Unfortunately this is the sort of accident that happens most commonly with chairlifts after getting stuck and evacuated.
Usually they'll stop for some reason, the brakes holding the cable in place fail, then the "heavy" side of the lift (the side with passengers) starts cruising backwards down the hill. The more people on the lift and the steeper the mountain, the uglier it will be.
Having said that, I've been a skier for my entire life and the only lift accidents I've seen have involved people falling off.