The idea is to keep you dry, not the floor. They are supposed to replace a bathmat and always having to wash i,t as bacteria aren't supposed to live on them for as long. In the shower room that kept flooding in France, we had to keep a towel on the floor and also use the duckboard on top of it, otherwise it was like paddling. So it did have a use, but I wish the owners had warned us. I think one would be fine on a wooden floor, or tiles that weren't slippery - and also get one that is quite big so that you don't step on one end and cause it to flip up. If you are fed up with washing bathmats they are probably not a bad thing, as long as they are well made. I just stopped using mine because of the flipping, having to pop it into the bath when I vacuumed (wooden floor in large bathroom) and because it was starting to look a bit mouldy. It probably should have been made of tantalised timber or something.