I also didn’t know about this. There’s a problem with features like these - casual user doesn’t even realize it exists, but motivated actors can easily exploit it to correct the conversation.
`flag` is visible on the submission list pages underneath the submission title. It's not hidden in any way. Next to it is also `hide` which is what most people should use for content they're not interested in but that may be appropriate for the site overall. `hide` is also not hidden.
> The basic algorithm divides points by a power of the time since a story was submitted. Comments in threads are ranked the same way.
> Other factors affecting rank include user flags, anti-abuse software, software which demotes overheated discussions, account or site weighting, and moderator action.
To be fair, "flag" is short for "flag for review for removal by moderators", and has been for decades on internet forums. Making flags also downvote is counterintuitive, to say the least.
And people don't usually read the FAQ to double-check that basic forum features work in the intuitive way. :)
