Yup, got it also, so it works.
I have some theories:
1. Inbox full
View messages: Inbox
Folder is 12% full (6 from 50 messages stored)
You can go to "Rules, folders & settings" and specify what happens with your messages if Inbox is full.
2. The planets are aligned very unfortunate, and everything goes wrong on Dave's profile.
3. Dave is a noob and can't use a simple forum.