![](https://pic1.mangapicgallery.com/r/avatar/eb/u81934_50x50.jpg?2)
I think it's just the type of audience they attract.
Someone who has an amazing taste in stories will probably read the crap stories and stop halfway through so they often wouldn't leave a rating...
plus the majority of the audience of shitty stories tend to be children (or early teens) so they have more time to actually rate the stories than older audience who have less time available because they're busy with life e.g. exams, jobs etc.
It hurts for me to see that masterpiece mangas like Uchuu Kyoudai were rated 9.7 here by a measly handful of votes. yet, there are some webtoons/manhwas, poorly lacking in story substance and depth which the only saving grace are full-colored pages and freakishly "good looking MCs', were rated 9.9 by thousands. The difference in the number of voters is by leaps and bounds. if it's not absolute madness, I dont know what it is.