If you are worried that people will get into your hotel room, keep a glass near the door handle.
There are some hotel hacks that work better than others for keeping us safe. Grab an empty glass, place it on your door handle and you will be sure that no one can break in when you are trying to sleep. If someone tries to break in, they will be disturbed.
The glass will fall on the floor when they move the handle. This should wake you up, and hopefully scare them away. We hope that no one will break in but we are now covered in case anything happens when we are away.