There is something about hotels, as these confessions prove, which seems to draw out the worst in people.
Housekeepers, bellboys and management staff from establishments all over the world have taken to an online forum to air their guests' dirty laundry - in some cases almost literally, the Daily Mail reports.
From leaving used condoms under the pillow and attempting to conceal blood-stained sheets, to urinating in minibar bottles and even defecating in a drawer - these hotel horror stories will give you a whole new perspective on what it's like to work in the service industry.
More than 500 current and former hotel employees responded to the online discussion thread: "Hotel workers of Reddit, what is something guests do that gets under your skin the most?"
One wrote: "Was a hotel room cleaner when guests put used untied condoms in the toilet, under pillows, under the bed, on the tea and coffee tray... basically anywhere. And not flushing the toilet. It's disgusting."
Another wrote: "Taking a s*** in one of the drawers and leaving it there."
And it's not only the cleaners who suffer the consequences of this sort of behaviour. In a handful of cases, it was the next set of guests.
One wrote: "We had guests open the mini-bar fridge, drink the beer, p*** in the empty bottle, screwed/put the cap back on and went on their merry ways.
"Next client (old gentleman with his daughter) took a swill of p*** that day."
This user added: "From that day on, I always twist beers open near my ear so I can hear that satisfying 'tssss' sound, just in case."
Another former employee from a different hotel revealed: "When I was a housekeeper, someone got blood all over the sheets in one bed in the room, made it up to look like it hadn't been used, and mussed up the sheets on the other bed.
"I was supposed to leave a bed alone if it hadn't been used, so I didn't know about the bloody sheets and I didn't change them.
"The next guest in that room arrived at 1am and crawled into the bed and fell asleep without even looking at the sheets. She saw the blood in the morning and was furious."
Several submitters mentioned feral children as being a grievance, one remarking: "B*****d jackal children running up and down the halls. Some even like to knock on other guest's doors at 10pm and shout 'housekeeping!' They honestly think it's hilarious."
In other cases, it's the parents.
"What got to me most was the number of times I was used as an example by parents when their kids were misbehaving," one revealed. "For example, if I was cleaning the windows and a child was being noisy nearby a parent might say 'if you aren't good and don't listen you'll end up cleaning windows for your whole life like this man'.
"Completely dehumanising, demoralising, and just a bit of a s***bag thing to do anyway. Happened so many times I lost count."
Several expressed their annoyance over guests answering the door scantily-clad or in some cases "masturbating so the keeper will see them".
And one wrote: "Sex. The amount of times a guest will have [...] asked for room service, only to decide to f*** straight after they put the phone down; leaving me stuck outside the door with that extra set of towels or walking into a room to fix something and seeing more than I ever needed to."
But perhaps the most obscure complaint?
One user wrote: "I worked at a hunting lodge as a housekeeper when I was in high school. I did NOT appreciate it when people left animal remains in the trash. So many bird heads..."