Look it may not be spelled out in some sort of snooty which knife do you use guide to morons but there are definite behaviour rules about lift use (aka elevators for you rare Yanks visiting them thar here).
The big one is no farting, even if alone, because you entrap it in the lift.
The other one is this. If the lift doors have closed - and you're on the outside - you don't hit the button for 2-3 seconds so that lift can head up. You fucking wait. Otherwise if you do hit it you open the doors again.
Lately people have been breaking this rule. You think the journey has started then PING the doors open and some sheepish fuckwad slinks in mumbling 'orry as they do so because they fucking know they did the wrong thing.
Lift etiquette. Obey it.