You'd be surprised just how much effort people put into using a message board to cause harm to others.

I was a mod on a reasonably large subreddit. One day, someone decides to post links to extreme and shocking images but make them look like regular posts. Delete, ban, move on. They come back with a new account. Delete, ban, move on, implement limits on new accounts. They would then spend months warming up new accounts, using them to write regular posts and messages, before doing the same thing. This was a thankless task and most regular users never realized it was even going on.

Then, on the other side, there were people who absolutely lost it when they felt you made a bad decision. I deleted a post asking for cash under the table work in a local sub, combined with multiple people offering what looked like clearly illegal work. Multiple regular members of the community went absolutely crazy, as if I had personally wronged them.

I enjoyed running the subreddit but I had to give up. The person who took over after definitely enjoys the power a little bit too much. That's what you get when it's a volunteer gig.