He Didn’t Know How To Was Dishes
In my first share house at uni, I lived with an American guy who would only rinse dishes. That doesn’t sound bad, but he wouldn’t ever scrub them, just rinse them and then put them in the cupboard. One day I got a cake tin out of a drawer, and it was absolutely covered in old moldy cake. Of course, I ended up washing every dish before I used it after I realized what he was doing.