My mother was always a vacuum freak. It made her feel like her nasty rotten place was clean or something just because she vacuumed the moment a spec of anything hit the floor (IOW, several times a day). As a result, she laid down a bunch of carpet squares in the kitchen and bathroom just so she could vacuum there too. I was still a kid but I vehemently objected at how unsanitary that was, explaining that vacuums don't suck up mold and mildew from inevitable liquid messes in those areas.
Sure enough, I visited her recently and took a peek under one of those squares to see mildewed and disgusting linoleum and moldy undersides of the carpet squares. Gross.