I found out on another subreddit that hotels almost never wash the coverlets on the beds, which sparked my curiosity.

What are some other things that are disturbing/interesting/unsanitary about hotel rooms?

Hotel staff respond:

I've worked in several nicer hotels (in Sweden) and here are some tips:

• The glasses for toothbrushes are not always washed since the cleaners are in a hurry, often they are just held under the tap and rinsed (if even that). Check for lip prints.
• If there is a coffee mug with freeze dried coffee, check to see that it's not been standing too long before using (lots of dust inside).
• The remotes for the TV are rarely cleaned.
• Many things such as fans, heaters and even bathrobes might be something stored in one place in the hotel, if you need something you should ask for it, it's not always in every room.
• Check the seals on the things in the minibar. I once had a guest who had drunk the whiskey and then peed in the bottle, closed it, and put it back. I've also seen candy three month past the exp date.
• Maybe everyone knows this, but if you want fresh towels you should put the towels on the floor. If you hang them they will not be changed and you'll have to ask for new ones.

• If you book a jacuzzi, be warned, the jet system is often completely clogged up with really nasty gunk.
• Use a towel or sheet on the chairs or sofa, a LOT of people sit on them naked. It's nasty but there is often a brown streak on the desk chair that no one think about.
• If you book a room with a tub, don't check underneath, that's a place some personnel miss to clean.
• If the cleaning is bad or you don't like the room, tell the staff right away. Check for things that are important before unpacking. That way you can often get a different room since little cleaning is required.