As I was using the lavatory this morning, I discover there is a piece of toilet-paper on the floor along the wall towards the shower. It wasn't there the previous time I was in the room. In fact, with the wall being open along the bottom (with the attendant risk that taking a shower may soak all our toilet-roll supply into uselessness, if one isn't careful), it is infact lying on the lowered part of the floor that is part of the shower - basically on the opposite wall from the actual lavatorial installation.
Before I leave the lavatory, I pick up this piece of paper, to flush it down. It sticks to the floor. I assume at this point that someone has blown his nose, or somesuch. I get the piece of paper off the floor. Indeed it was used - but not for blowing anybody's nose. And (as mentioned above) positioned in such a location that when showering, water will flow over that spot and then towards the drain, which happens to be where one has one's feet when showering in this shower.
This is the point at which I run crazy with disinfectant spray and cleaning-fluids heavy on ammonia (strong enough that the fumes caused me to have to evacuate the bathroom afterwards).
I really do not need surprises like this in the morning.