why moderators are there. they are there to help people despite popular beleif,
When you get past the smoke and mirrors, and the innate fear of moderators, you find out what moderators are really there for. They are there to PROMOTE healthy discussion. No more, no less. All the tricks of the trade such as editing posts, locking threads, and yes even the mighty banhammer are ultimately there for the purpose of promoting a healthy discussion.
The idea of locking a thread is counter-productive to discussion. The discussion dies when the thread is locked. Therefore this tool is to be used only when the discussion is either inherently unhealthy (discussing how to rob a bank) or an otherwise healthy discussion has degenerated past the point of salvaging.
A good moderator uses the tools of locking/deleting/editing/banning like a surgical scalpel. You try your best to cut away the disease and leave the maximum amount of healthy tissue intact.
Most people see the moderators as the people who end discussions. And in some cases we have had bad moderators here who didn't understand their own function and did exactly that. But an ideal moderator will instead encourage discussion and steer the less worthwhile conversations back to the point of meaningful and healthy discussion.
Power-hungry moderators are poison to any forum. They rule the powerless underlings with fear and make a sport out of locking/deleting whenever they feel like lashing out, rather than when an actual rule has been broken. I've seen some people get banned out of sheer spite (maybe not so much here at this forum). The last thing you want is a moderator who wants the position for the fun of having mod powers.
Maybe the best analogy for a moderator is a traffic cop. Yes, he's a cop and could possibly arrest you, but that's not what he's there for. The point of having a traffic cop (in a city like New York for instance) is to facilitate the flow of traffic. He doesn't want gridlock, or cars backing up. His job is to get as many people safely to their destination as possible.
Likewise, a mod has the job of trying to get as many people engaged in the healthy exchange of ideas as possible, in the form of discussion threads. Unhealthy discussions (illegal activity, spamming, flaming, outright noobery) lower the intellectual level to the point where worthwhile discussions are no longer possible. The mod has to find a way to prevent such discussions while promoting good discussions that raise the level of discourse to the level of being meaningful, worthwhile, educational, helpful, etc.