[Nesco]

Except that on 4chan people adapts and mostly reads threads that already possess replies. The multiplicative effect it creates ensure that only the threads that are the most interesting get most of the views. And because it is an image board a similar effect happens for posts: the presence of an image and the length of a post give a quick proxy to evaluate the effort put in it. Yes it will never be as effective as a karma / like system but imo it’s well suited to an anonymous imageboard, particularly for boards where threads without replies tends to get replaced quickly.