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?
Well, imagine someone opening the door if the water hasn’t fully drained out and the ensuing mess. If you’re wondering if someone is stupid enough to do that, then the answer is unequivocally yes. There is a reason the door locks for that amount of time - so somebody doesn’t brain fart, open the door, and flood the laundry room.
So why not make the washing cycle end when the water has fully drained? I get the impression the timer starts after the drain.
Maybe that’s your machine being oddly programmed. Every machine I’ve seen unlocks right after it finishes it’s cycle. It can also be stopped and unlocked anywhere halfway, but it takes some time to drain the water (usually a few seconds, not a full minute like you mentioned originally).