Unintelligent Design

...I agree completely. The thing with him is, he doesn't change. Pretty much everyone else has - Vimes, Carrot, Death, Susan (even Granny Weatherwax!). Especially the one-book-only characters. Whereas Rincewind starts and ends every book the same way. Although usually on a different continent. Twoflower got some character development in Interesting Times, as did Cohen. But Rincewind? He's a plot device on legs, I'm afraid.