A superficial rating site that doesn't genuinely take in account the quality of the class or teacher. Example if a teacher sexual harass a student or eats in class, the site will still give high rating as long as they have the minimum of Easiness/Helpfulness/Clarity/Rater Interest. Apparently integrity is not factor at the site.
It is also easy for teacher not to take accountability. I notice teachers with consistent bad reviews over months or years seem to have them magically filter out or disappeared. This defeats the purpose of the site, or honest recommendations. This is disservice to student or really hard working teachers who earned their score.