I lurk and post once in a while. What I’ve noticed is that rarely is something downvoted for being factually incorrect (relatively speaking). You just have to offer a perspective that doesn’t conform with the hive mind and the downvoting essentially amounts to censorship of opinions.
When I see heated back-and-forth discussion chains I'll often find myself downvoting several comments and upvoting none of them, because sarcastic quippy retorts to bad comments are also bad comments.
I'll also downvote comments for factual inaccuracy, particularly if I don't have the time to patiently correct them. This only partially mitigates the damage and doesn't really help the original author to learn. When someone writes a comment with just a single big mistake, and they don't seem to have a history of willfully repeating it, that's when I am most likely to write a lengthy reply with explanation and citations.
I once made a post that criticized the Anglocentric perspective of an article. — it was initially upvoted, but then became downvoted when UTC+2 went to sleep, and then upvoted again when UTC+2 woke up. — one can take a particular guess as to why.
Despite whether I agree with it, I upvote anything that I learn something new from.
Factual incorrectness is often downvoted, but usually only if there is a reply that points it out.
If downvoting bad comments (for any definition of bad) was harder or even outright impossible you'd still have an alternative: upvote an other, better comment to have it shadow what you consider a less valuable contribution. And that's a positive interaction.
Whenever I find a comment that I think is on-topic and somewhat constructive, but I still fundamentally disagree with the take, I generally go hunting for a comment that embraces my point of view (or write one myself) and upvote that.
I very rarely downvote comments on this site, and generally only do it for comments that I consider to be completely off topic, flamebait or stupid "meme" references. That being said I do comment quite a bit and I admit that I'm always a bit frustrated when I take the time to write what I consider to be a constructive (if sometimes controversial) comment and I get downvoted reddit-style. It feels disrespectful, almost. I probably care too much about that stuff, I acknowledge that.
that's ok, the onus is on the downvoted poster to figure it out for themselves. usually that requires seeing a pattern over the course of a few downvoted posts rather than pinpointing it exactly from a given post.
most downvoted posts break one or more hn rules, but a few are downvoted ideologically, so a little resilience is required. strictly unpopular opinions can often be more tactfully rephrased and at least be accepted for discussion, if not agreement. this is a pretty good life skill to develop generally anyways.
Presumably the onus is on you to figure that out, but good luck, since I'm not sure either and usually I can tell.
- You can earn points but never lose them by submitting URLs for discussion.
- You can't lose more than 4 points per post, no matter how many times it is downvoted. There is no upper limit to points gained from a single upvoted comment.
- There is only a 24 hour time window in which comments can be downvoted, but they can still be upvoted even months later.
The expertise problem is harder. Sometimes I see a post that has more misconceptions than sentences, but is grammatically correct and written in a confident tone. Only people who actually understand the subject matter will spot the problems quickly. It's tedious to write introductory level corrections for commonly repeated mistakes. For some of them I have considered keeping a mini-FAQ locally and pasting standard responses to standard misconceptions, but HN also discourages repeating identical posts.
If I downvote a misinformed post the original poster won't know where they went wrong, and people who see a grayed post won't necessarily understand what's wrong with it either. The saving grace of the downvote is that it affects comment sorting order, so at least misconception-heavy posts that are downvoted won't dominate the upper reaches of the discussion page.