Perhaps it’s for religious or superstitious reasons, but many guests request to stay in the same room as they did during a previous stay. Some users on Reddit who work/worked at hotels mentioned that such guests often hide embarrassing items like porn and blow up dolls in unusual parts of the room.
Hint: Look under the mattress of your bed. There's bound to be something.
4. Making a disastrous mess in the bathroom
Like crapping in the wrong places and leaving behind things that are destined to go to the rubbish bin. I'm not even kidding. God bless the housekeepers who have to deal with this on a daily basis.