You can ask a million times (although DON'T), but it isn't asking that gets you to be a moderator. You have to prove that you would be good at the job by being helpful at all times and unflappable in a crisis.
Memnoch didn't just walk in and say, 'hey ziroc, give us a job mate'. He got the job because he is level headed and helpful - ideal moderator material.
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Time is an illusion. Lunchtime doubly so.
Epona of The Laughing Hyenas