I've explained a little about downvoting in other articles of POB street. I use the DV to remove rewards from fraudulent articles. People can use the DV to remove rewards for over-rewarded posts. One flaw of Hive is that there is no clear governance on the use of up or down voting.

A consequence of a lack of governance is the formation of groups like HDR and Hivewatchers.

Upvoting is used to reward articles. Downvotes are used to remove rewards, return it to the supply, and stabilize the impact of malicious upvoting. Unfortunately, downvoting is used in a cavalier manner too and upvotes can be as well.