You get to downvote if you get enough karma from your posts being upvoted. But a certain fraction of users seem to get a power trip from this, and downvote absolutely anything that doesn't tickle their fancy just so.

Please don't take downvotes on innocuous comments personally. Someone will come by and randomly downvote. Why? Who knows? A few minutes later someone else will restore the balance. On the other hand it's really annoying to read complaints about downvotes.

> Please don't comment about the voting on comments. It never does any good, and it makes boring reading.

https://news.ycombinator.com/newsguidelines.html

You need to have karma above a certain threshold. It used to be > 500 (not sure what it currently is) https://github.com/minimaxir/hacker-news-undocumented#downvo...