In my experience, up/down votes correlate more closely to agreement/disagreement than to whether they are good or meaningful. Knowing the audience of HN is ofte

In my experience, up/down votes correlate more closely to agreement/disagreement than to whether they are good or meaningful. Knowing the audience of HN is often more important than adding to the discussion. That doesn't mean that good or meaningful comments are useless. But if you do present a good and meaningful argument that goes against the majority, you will often be silenced. This frequently results in that person deleting their comment as the downvotes accumulate. I'm not sure how this is accounted for in the statistics of the site.