Further quoting from the Parenting call for moderators:
Remember, this is a strictly volunteer activity. We know that folks have lives, taking a break whenever you need to is perfectly fine. All we ask is that you let us know if you think you might be gone for an extended amount of time. No part of the job is compulsory.
Stack Exchange has only a few requirements that we place on moderators, which are described in the Moderator Agreement. Generally, these requirements focus on protecting personal information. We reserve the right to remove moderators and have done so in the past. In practice, we usually remove moderators when they let us know they are no longer interested in the job.
Over on Stack Overflow, we've talked about a Moderator Standard of Duty:
While none of us committed to a certain level of participation when accepting our agreement, I think that we all understood that:
- Moderators should want the responsibility
- The main part of a moderator's job is to attend to flags
I can't conceive of someone wanting the responsibility unless they visit and use the site on a regular basis with plans to continue doing so.
One of the standards Tim suggested was to handle "an average of 60 - 100 flags per week." To put that in perspective, Islam.SE got 98 flags this past week. That means that the site's flags could easily be handled by just one moderator and it has four. So it's not unusual to come to the site and find no outstanding flags.
On a small site, like this one, we don't expect moderators to have a particular "standard of duty". Rather, we ask that they work together as a team to handle the thornier issues that come up from time to time. Flag handling, which is the main part of a moderator's job, is not actually all that taxing on this site. What usually takes moderator time and effort is making the tough decisions about how the community should operate. In all, the Islam Stack Exchange moderators are doing a bang-up job.
If some moderators are inactive for extended periods of time, we send an automated email reminding them to let us know if Real Life™ prevents them from performing the job. If they remain absent for six months, we invoke our Absentee Moderator Policy. Otherwise, we don't really worry about individual moderators so much as the entire team.