What are some pet peeves about maps? Or maybe common mistakes?

I think one of my peeves is when the book gives a world map, it is labelled as a world map, and yet there are only two and a half countries (if that) on this world map. And these countries have approximately two cities and three towns between them. Or there is a castle, a battle plain, and the den of the Evil Overlord, and nothing else. It's more a failure of world building than any fault of the mapmaker usually, but it still makes me not believe in the world a little less when I see a map like that at the front of the book.

Another minor nitpick is when they show a map of the world and it is all terra firm with nowhere near enough water.