Took 2 years to realize my roommate's recycling bin was actually my garbage can
Moved in with a guy who had a tiny black bin next to his desk. I threw coffee grounds in it every morning for two years until he finally asked why I kept using his paintbrush cleaner. He was dipping brushes in it, not trash. Has anyone else confused a roommate's hobby tool for a household item?
Real talk though, paintbrush cleaner and coffee grounds look nothing alike. Two years is a long time to never once look inside the bin and notice it wasn't filling up with trash like a normal can. Sounds like you both needed to pay more attention to what was happening a foot from your faces.