Usually it’s a “you’re an asshole” button.

When content is low quality, posted to the wrong community (usually intentionally), trolls. Basically anything that I feel shouldn’t exist. The content that I believe takes value from people’s lives instead of adding it. If I find content that I dislike but believe adds value to other people, well that’s what the block/ban features are for.

These days, mostly for reddit mirror bots.

I dunno what people’s obsession is with Lululemon, and I really don’t care, but that fucking bot alone is like 5% of lemmy/all, these days.

For me it’s “this comment shouldn’t exist” button. Sometimes it’s because it makes the experience of reading worse, regardless of the content of the comment. Sometimes it’s because the content is so bad.
But i don’t just downvote something if I just disagree with it, it should be bad

I use it for

1. Not relevant
2. Needs editing for writing mistakes.

To add a little colour to my front page.

Silly OP, I don’t even have a downvote button (idk if it’s the instance I’m in but I don’t particularly mind ngl)

To order a delicious sorbet.

The downvote button is the disagree button

Bad faith arguments or inflammatory nonsense. We can disagree and I’ll upvote if you’re actually speaking in good faith.

Pretty much any form of, “Whataboutism” gets downvoted. No one was talking about C, why are you acting indignant about C when people were discussing A and B, you know?

I like to reserve it for special occasions. Comments that are very confidently wrong, needlessly edgy or rhethorically loaded. Anything that I don’t want to dignify with a verbal response but where I still want to express my aversion. The exception are “funny downvotes” like mass downvoting the fourth person in a chain or stuff like that.

I disagree, so I downvoted you. Guess that’s my answer.

“This”

Not your post, but anything that’s just an upvote in the form of a comment.

Also anything that’s egregious misinformation or bad faith posting.

Or anything that’s just spammy or bonkers crazy. I’ve blocked more people in my 1-ish year on Lemmy than I had in something like 10 years on Reddit…it definitely feels like Lemmy is the haven for Reddit refugees, including those who got banned for not really understanding how to engage in this type of space.

Also, any post that really doesn’t fit the community. Like NoStupidQuestions posts that aren’t questions or are really just AITA or DAE (social validation) posts in disguise.

I know that sounds like a lot, but for the most part, I don’t vote on things. I upvote most posts that are cool/interesting enough to get me to go to the source or read through the comments, as well as any good comments. And pretty much any comment that engages in discussion with my own comments without being annoying or rude, lol

I don’t have a downvote button but if I did I’d use it on misinformation. Things that are factually incorrect or unsubstantiated.