Male Cleaning

I found this sign when I went to use the bathroom the other day when I was out. The bathroom door definitely had a female sign on it so this sign placed on the ground in front of the door intrigued me.  Is it so rare that a male is cleaning a toilet that it requires a sign?  Was there a male in the  female toilet cleaning himself therefore I should stay out?  Was the sign a declaration that demanded women should stand about and give a resounding clap when he exited the toilet? Perhaps this was just a good humored male cleaner whose wife had brought him a sign because she was proud of him?  Whatever the case, it made me chuckle but I didn't go in.