Comment by sytelus

A large community often contains many subgroups. When a system allows any subgroups to take over and represent their sentiments as community's sentiments, the community starts to breakdown. To avoid this system needs to allow enough expressiveness. This would mean at least a upvote button as well as downvote button. By only allowing upvotes, HN steals away expressiveness of the community. Any jealous subgroup can essentially upvote a story they had like others to read and get it on top while other members of community have no recourse but to upvote something else and spread their expression thinly. We have seen this many times now. I can see marketers and activists coming over to HN and push a story on top with as little as 100 upvotes while rest of the community just sits back unable to express their preferences.