Every other time I see a "wet floor" sign the following idea comes to my mind. That sign forces me through unnecessary mental effort to deduce that wet floors can be slippery.
I think it's like providing a set of differential equations that describe slippery floors and expecting that everyone recognizes them and deduces that there's danger of falling. The sign actually means "man, the floor is slippery, you can fall and break apart" and IMO it could just read "slippery floor" instead.
Is there any reason why those signs use "wet floor" phrasing?