Comment by Shog9

Crucially, SO's election system needs to be bootstrapped: users aren't eligible to vote until they have a history of participation. The level of participation is fairly trivial, but it provides enough signal to allow a reasonable detection (and elimination) of bot / sock puppet networks without resorting to crude measures like blacklists or "bot tests".

For new sites, this meant that the bulk of moderation was done by employees, followed by employee-appointed temporary moderators. This dramatically reduced abuse, but also reduced the explosion of new sub-communities that sites like Reddit thrived on.