Moderators were appointed to deal with some horrific trolling. For example, at one point the full names and addresses of up to a dozen posters were displayed late on a Friday to intimidate them, and at the time nothing could be done about it until the magazine staff were next in the office on the Monday morning.
We also had the usual online personal harassment issues. Can't remember how many times I received sexually pestering PM's from men I only knew as (say) Satan's Hoof or LoveMadgickeMan. As there was nobody to report them to and no way to get them booted off, and no 'Ignore' function, I'd just decline to respond.
Even saying 'Get lost!' was engaging with them. We were powerless against these vicious idiots.
One particular troll, whom I will not name or otherwise identify, harassed women on here and even followed them to other boards. He was manipulative and persistent enough to compromise some of them.
By the time he demanded that I take a holiday abroad with him as I'd publicly promised (I'd done no such thing of course) I knew of his tactics. When he threatened to turn up and claim me in person I told him yeah, you do that, and Techy will punch you up the bracket.
One woman he'd chased to another board was so frightened when he told her he was on his way to visit, she posted on the board asking for help.
There's a lot more to tell about him but that's enough to give an idea about why we needed moderators. A very fine job they do too.