This was my first submission, and the above comment was what I added to the text box. It wasn’t clear to me what the purpose was, but it seemed like it would want an excerpt. I only discovered after submitting that it created this comment.

I guess people just generally don’t add those?

Still, to help me out, could someone clarify why this was down-voted? I don’t want to mess up again if I did, but I don't understand what that was.

I think its just because as a comment it looks pretty random and somewhat off topic since its a summary of the article instead of an opinion on it.

I think most of the time people dont add a comment to submissions, but if they do its more of the form: I found X interesting because of [insert non obvious reason why X is interesting] or some additional non-obvious context needed.

In any case, i don't think there is any reason to worry too much. There was no ill intent and at the end of the day its all just fake internet points.

I don't know, but I see early posts which look like AI bot summaries (presumably to collect karma). Probably not necessary for a link.

> Leave url blank to submit a question for discussion. If there is no url, text will appear at the top of the thread. If there is a url, text is optional.

Most people will opt for text to be optional with a link - unless they're showing their own product (Show HN). Because there is an expectation that you will attempt to read an article, before conversing about it.