Some good articles get no upvotes due to bad luck. Some are reposted and the repost get more traction. Sometimes another source cover the same event and get traction here.

From time to time there are attempts to use bots/sockpuppets/meatpuppets/shills/whatever. Most of the time the system detect the attempt, or the users detect it and flag the article or write mean comments (not very mean because dang may ban your account if you write mean comments).