Why does the moderator have to approve my post?

Just wondering. I've posted guns for sale here before, but the last gun I posted, I got the message that the moderator would have to approve my posting first.

The website sometimes gets confused and thinks valid posts are spam. On the plus side, it does catch a bunch of the junk. The down side is it will occasionally block things like yours.

Thanks for the reply! Funny thing, I tried again today and I was able to post!