We've all known that person who cannot clean up after themselves in any shared space. When I was growing up doing community theatre, there would always be somebody who would leave their stuff around an already messy dressing room. No matter how often we were told to put our costumes and makeup away, somebody would leave some dirty tights and jazz shoes on the floor for someone else to slip on later.
Sometimes, people are messy because they're just young and careless. I had my fair share of moments of leaving my shoes on the stairs, even though my mom told me to take them up to my room a thousand times. Other times, people don't clean up after themselves because they're careless and assume that somebody else will take on the load without complaints. That only leads to bitterness and resentment from the person thanklessly picking up after others.