Time is precious.

The issue I have with HN (and other Forums), is that there is a lot of repetition in the comments. In part on HN this is probably not helped as it's difficult to overview and digest threads, especially if the comment trees are large. Comment verbosity and positional changes also make it difficult.

I think that is why in part people come, post, then move on. Necro-posting, even a day late is pretty pointless if you want to add to the general discussion.

I think I'd rather comments have a character limit. Or to get people to post summaries of their posts as titles. And/or some tl;dr; post mortems on comment threads.