There are countless studies showing most office desks are dirtier than a toilet seat (just type in “desks are dirtier than” into Google for examples). Gross! All these germs and grim will eventually just make you and the rest of your office mates sicker over time.
Now that we’ve established the importance of keeping your personal space as germ free as possible, it is just as important, if not more so, to clean up after yourself in the office break room. No one wants to clean up your coffee spill or rinse your dishes. At best, you’ll be known as the office slob. At worse, the irresponsible co-worker employee.
Posting passive-aggressive signs in the break room won’t convince sloppy Sally to clean up after herself. However, neither will just leaving the dishes to mold and smell. If this is really an issue, I suggest talking about it with your supervisor and asking for their suggestions on how to address the issue.