My oven can't be left on. You always have to dial in a duration for how long it should be on, along with mode and temperature. Timer runs out, it turns off. It's a good safety feature.,
Unfortunately being used to that, every time I've used someone else's oven, I've forgotten to turn it off.
I left.the oven on for about 48hrs once when went away only damage was to my pocket from the electricity bill (and wasn't that bad as quite well insulated, was maybe about £30-40 (so double for the month) (few years ago)
Ive left on one oven plate over night one time. I had luck nothing stood on it. Now i never stack anything on them, i think this is a huge improvement safetywise.