One of my moderator colleagues recently imposed a review ban on a user. I knew about it because I discussed it with him before he imposed the ban. However, I was somewhat surprised when I didn't receive a notice of the review ban in the moderator inbox. Why aren't such notifications added to the moderator inbox?
As far as I can tell, the moderator inbox is only used for (a) new questions on the site meta and (b) suspensions/moderator messages. While a review ban is less serious than a suspension, a notification to other moderators seems like it would be useful. At the very least, it would help the other moderators develop a mental list of users to keep an eye on in the review queues (since the system doesn't provide a list of previously banned users).
I'd guess that the main reason not to notify moderators of review bans is to avoid cluttering up the moderator inbox. However, I'm a moderator on a medium-sized site and there are so few review bans that I don't think that would be a concern (except, perhaps, for the biggest sites). Then again, how would I know how many review bans are imposed if I'm not notified of them? Are there statistics on how many review bans are imposed (either manually or automatically), especially on the bigger sites? Are there so many review bans that notifications for them in the moderator inbox would be too much noise? Or are there other reason(s) why the moderator inbox does not include notifications for review bans?