Manual moderation works for small communities and fails predictably as they grow. Here's why, and what actually holds up at scale.
In a small group, an admin can realistically watch every message. This works fine until the group crosses a size or activity threshold.
Past a certain size, spam happens faster than any human can catch it, especially outside normal waking hours.
Pattern-based and rate-based detection catch the large majority of low-effort spam and scam attempts automatically, in real time.
Judgment calls still need a human. Automated moderation is best designed to remove high-volume cases and flag ambiguous ones.
Automated detection for known patterns, real-time alerts for anything ambiguous, and a clear log of automated actions for admins to review.