When we were young, poor, and renting, my husband was always a slob; he never picked up after himself, left his dirty and clean clothes together in a mountain on his side of the bed, would rather die than wash a dish, etc. His car was putrid. As a medium clean person (but not a neat freak), I was annoyed by the clutter and grossness.
My sons are married and live quite a distance from me. I try to visit several times a year because I want to see my grandchildren as often as I can. Sometimes I stay with them; other times I rent an Airbnb. The problem is that I am a neat-nut. When I'm at their house, I empty full sinks of dishes, clean bathrooms, sweep floors, polish mirrors/windows, dust furniture, etc. I'll even do laundry if they want.