Most of the flagged comments I've seen are low quality, off topic, or violating the code of conduct. Flagging is a mechanism of distributed moderation. And ther

Most of the flagged comments I've seen are low quality, off topic, or violating the code of conduct. Flagging is a mechanism of distributed moderation. And there is a system where high-karma users can vouch for a comment and have it reappear. Also, anyone can opt in to see flagged comments. So they aren't being completely hidden off the site unless they get nuked from the backend.