Why can't the hotel magnet swipe door be locked?

If people outside have room key cards or master cards, floor cards, etc. The door lock can be opened. No need to lock, there is a key card outside to open. It's locked, even if there is a key card outside, it can't be opened.

If the room buckle doesn't work, you can ask the hotel to change rooms, or repair the buckle to a carpenter. You can't buckle it from the outside. If you are sure that someone has come in, you can close the door and reach for the stool behind it. Get up in the morning to check the displacement of the stool, and you will know if anyone has come in.