@Farwa-and-Raza0
Some people will do load after load, some will think it's ok to start a three hour cycle at 3am.
Some will wash a miniscule amount every day. People will use wrong doses of detergents...etc
If any of these incidents are likely to agitate you, take action to control it.
Put a lock on the plug or isolate the machine from the power, put up a sign to explain it is strictly off limits to guests and not on the amentities (this will stop 80% of the requests but not all), show where they can find the nearest laundromat and hide your detergents.