Depends on how you look at it.
Some maps are made as a joke, or just for fun, and they should probably be rated as such. This map is no worse than Granger-rink, which, is actually a good map. Foto also falls into this catergory.
Some maps are semi-serious, and are intended for some game-play, but were not intended purely as such. Say, highrise, or perhaps Watah.
Some maps were intended for serious gameplay, but fail miserably. We all know what these are. I am not mentioning names to avoid getting lynched.