Does anyone know the guidelines of when to flag submissions? For me, submissions that spread misinformation should be flagged. But just because you don't agree

Does anyone know the guidelines of when to flag submissions? For me, submissions that spread misinformation should be flagged. But just because you don't agree or like the article, doesn't mean that you should flag it. I guess this submission is flagged because some people don't like it but HN doesn't have downvote button, so they use the flag button as an alternative.