Originally Posted by
squirtdad
There is, in my hands on experience, a huge world of difference in quality between high end and low end twist shifters in areas such as durability, function, materials
I am not against twist shifters, but have lot's of experience with cheapo ones on BSO from big box stores. They simply don't work well or last, especially combined with the over all low end level of components overall.
I think there is a room for excessive force required when the interior flexes too much and the pull of cable simultaneously forces the moving part rub against those stationary. Looking closer at the quality of components on the bike, I am not sure changing any single one could improve the general situation.