Why is there so little Expressionist architecture?

From the Wikipedia article on Expressionism – http://en.wikipedia.org/wiki/Expressionism:

That’s it? Only three examples, one of them doubtful?

Is there something about the Expressionist esthetic that doesn’t translate well into architecture?

Because crazily slanting walls, painted-on shadows, and teeny misshapen windows tend to freak people out?

Your cite is more a reflection on Wikipedia’s limited usefulness than on the state of Expressionist Architecture. Google the term for more examples.

Since lissener couldn’t be arsed, here’s a survey, with pictures. Not all Expressionist architecture was German. There’s Gaudí in Spain, for example.