Hello elevator expert! I totally believe you about elevators being usually very safe. The few scary cases I've heard of do not involve the elevator plummeting with people inside, rather that as someone entered or exited the elevator malfunctioned and started moving, resulting in serious injury or sometimes death. I saw a (blurred) video of it that was from China, and maybe that was due to lax building codes, but there was also a case of it in America about 10 years ago where a malfunctioning elevator was poorly labelled and wasn't cordoned off properly, and somebody tried to use it and was trapped when the elevator moved as she was half in the doorway. Do you have any idea what causes this malfunction? I assume it's extremely rare in places that have proper building codes.

A functioning elevator has a light beam or light curtain (= many beams) in between the doors to detect if someone or something is in between the closing doors. These prevent the door from closing on you when you are getting in or out. There is also a locking mechanism in the doors which actually trigger a switch which enables the elevator to be powered. If the doors are open, the switch is open, which breaks the safety chain which then prevents the elevator from moving because it physically prevents the current from moving through the circuit. When the doors are closed and locked, only then the elevator will be able to move. The doors of the car are also coupled with the doors on the floor landing, and only the elevator car doors have a motor. This means that the doors on the landing cannot open by accident, when the car is not there - the landing doors only open when the car is there and attached and locked to the landing doors, as the opening of the car doors opens also the landing doors. So why these things sometimes still fail? A bit hard to say. Some older elevators don't have all these safety features in place. Also, I am sure with enough creativity a maintenance technician who does not know what they are doing or wish to cut corners can disable some of the safety features. Sometimes, to save cost, building owners opt to buy maintenance from private small "man and a van" type companies rather than from the company who manufactured the elevator. Not saying of course that all small companies would be bad or that big ones wouldn't make mistakes either. Did I answer your question at all?