I think if you've never left the USA you would obviously think that there was some sort of conspiracy to install fake elevator door close buttons, since there is absolutely no feedback in the system that would help an uninformed layperson realize that the door IS closing but on a several second delay. When I lived in China, EVERY elevator door close button worked, and worked instantly. This led to exactly the behavior you would expect, of selfish people getting in elevators and immediately shutting them to hurry on towards their destination. This is not possible in America, where the ADA requires the 3-second minimum delay explained in this article so that e.g. people in wheelchairs have time to get into the lift. So it's not the case that our American elevator door close buttons are placebos, but they ARE doing a terrible job of informing users what they are doing and why.