Welcome to South Park Answers. What would you like to know?

Butters was simply more popular. Tweek was a last minute choice to replace Kenny (source: commentary of the "professor Chaos" episode), and I think the creators grew tired of Tweek after a few episodes. And Butters already was very popular, and has remained popular with the creators of South Park ever since.

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.