Lack of spontaneity may not get the list fired up, and this lack of engagement may not deliver the kind of value an unmoderated list delivers. Highest quality form of discussion list where list members are virtually guaranteed that every post will be on-topic and of value or possible interest to them. Lowest amount of risk and near-zero liability because all viruses, porn pics, vulgarity and anything else the moderator wants to censor are removed before the list members even knew it existed. Higher CPM or larger ad buys are possible because many of the big firms that have large ad budgets will only advertise on fully-moderated discussion lists. Semi-Moderated discussion list.
Inappropriate behavior is dealt with quickly and folks who abuse the list are banned or removed.
Bad things can be passed through the list or an autoresponder loop can go undetected. Thousands of emails could fly before the moderator steps into the ring to solve the problem. Very high level of quality because the forum is watched daily and the list members are virtually guaranteed that every post will be on-topic and of value or possible interest to them. High levels of list member engagement and interaction can be achieved, resulting in a higher quality forum. Lower list moderation human time costs because the list is overseen and not approved by post.