Re: Why is “modship” taken away from some members?
As Muzna said, they dont need to be at a certain membership level, but for most of the part, level of activity over a longer period of time is a qualifier. That means that keeping everything same, I would pick a person who is actively posting from last many months but may have only 2000 post, vs someone who joined 3 months ago and hit 3000 posts.
As for the process goes, here is how bring a person in.
Our first choice is to pick a person from existing team (so if we need a mod for Cafe, we look for one within mod team). If we need to bring a person from outside, then Channel Manager of that forum looks for people from members and identify 1 or 2 and then starts a thread in CM forum. Every proposed name needs to get 3 yeses and 0 Noes (even 1 no supersedes all the yeses). Once it gets 3 yeses then the CM sends out a PM to the that member and offers him/her moderator ship.
As far as Mods leaving the team is concerned, 95% of them resign because of the facts that Muzna mentioned. Only maybe in 5% cases where admins take the decision that the team is better off without this or that mod.