Update: Kevin Montrose makes it happen
The hell-ban is no more! Long live the verbose, obnoxiously evident ban!
Kevin has implemented (more or less) the system described below. Flaggers with a recent (past 7 days) flagging history consisting of at least 10 flags where >= 10% of flags were declined will see the following when they flag:
Those who've had 25% or more of their flags declined will see:
...and will be unable to flag any further posts for any reason.
Folks who've flagged fewer than 10 posts in the past week whose most recently-processed flag was declined will see:
Flags considered for the purpose of these warnings / bans are currently limited to post flags which often require explicit moderator intervention: Other, Spam, Offensive, Very Low Quality, Invalid Flag, Close and Not an Answer. I'm not 100% on the value of including close flags in this: we spot-tested these criteria with and without them at various times, and the downside to including them is that they can end up making some folks' flagging histories look better than they appear to the moderators. However, these are listed on the flag summary page that's linked to from the warnings, so for now we'll include them and see how it plays out in practice.
Hopefully, this will help less prolific flaggers learn to use the system correctly without repeatedly wasting their time and that of the site moderators.
We'll be keeping an eye on this and adjusting these thresholds as-needed. Please report any problems you encounter here on meta, using the tag declined-flags.
We're in the middle of a major re-write of the entire flagging system. As part of this, we're re-thinking how flag weight (and thus "hell bans") work. Anna & I have been discussing this for a while - here's what we're looking at doing instead:
Only look at folks who cast at least 10 flags a week. There isn't much point in doing much to knock the priority of flags from people who rarely flag anything.
If at least 10% of your flags from the past 7 days were declined, you'll get a little warning next time you go to flag something... Along with a link to your flag history so you can see exactly where the problems arose.
If at least 25% of your flags from the past 7 days were declined, you're blocked from flagging anything. Depending on when and how those declined flags were cast, this block could last for as little as a day, and won't ever be longer than a week.
For users with less than 10 flags in the past week, look only at the status of the last flag - if it was declined, then warn as above (but with the message "Your last flag was declined..."). This handles the case where new users are confused as to what "flag" is supposed to be used for.
Over time, the flag system has evolved from a rather opaque "I saw a problem, please do something" system into a way for everyone to work hand-in-hand with the elected moderators. For this to be effective, it must include feedback on how well you're flagging - closing that feedback loop should help our more prolific flaggers to become better at flagging, and reduce noise for the moderator teams.