You can usually get a lot of useful and interesting information from the comments on HN submissions even if you don't or can't read the article.

Often, top level comments aren't even really about anything in the article. The article reminds the commentator of some tangent and they comment on that tangent. That top level comment and its comment subthread are in effect a separate article and its comments.

It's often these tangents that make HN comment threads worth reading.