Most washing machines have a timer that prevents you from opening the hatch just after the washing cycle ends. Instad you must wait for the timer to go off, usually a minute or two, before you can open the hatch.
Why? Would letting the user open the hatch immediately after washing ends pose any safety or other issues?
Mine beeps and simultaneously unlocks the door. Beeping befor you can open it truely does sound stupid… Never had that with any washing machine here in Switzerland though.