Flanderization

Flanderization is the process through which a complex fictional character's essential traits are oversimplified to the point where they constitute their entire personality, or at least exaggerated while other traits remain, over the course of a serial work. The term Flanderization was coined by TV Tropes in reference to Ned Flanders of The Simpsons, who was caricatured over the show's run from a friendly and good-hearted neighbor (among other characteristics, while maintaining his Christian faith) into a dogmatic, evangelical "bible-thumper". Flanderization has been analyzed as an aspect of serial works, especially television comedies, that demonstrates a work's gradual decline.