The elevator thing is interesting.

At first, you just would think it works on a delay.

People notice that they don't really do anything. Rumor spreads that the buttons aren't even wired.

Eventually I remember coming across an article that explained most of the time it's a glitch. The button is telling it to close, but there's some kind of timing limitation that means the auto-close just happens first.

But yeah, for both I'm sure there's a lot of variation.