Some companies game the voting system on HN. You only need a few/dozens accounts with 2000+ karma to create group thinking by down-voting non-popular opinions that may harm the reputation of the company. We can regularly see this behaviour from a certain company from Redmond, their news on HN are heavily "moderated", and "not so great" news about them get flagged from the HN frontpage in no time and at the same time they release another "nice" news blurb that gets many votes in seconds. The HN users were more in favor of the competition, and since Build'15 a swamp of new HN accounts got created to form the opinion about new products, and give them a positive spin while on the same time hide and downvote all true comments about the evil spy features of their OS v10 and their other newer products that cannot be turned off by end consumers.

HN needs more logging to detect such coordinated (down-)voting rings to avoid group thinking and opinion shaping orchestrated by bad players.