We had a package fail completely (0 success records). I received the notification which was sent to email@example.com but my colleague did not receive the notification, even though he is an administrator and specified that the notifications should be sent to him. This has happened repeatly now, and he hasn't received any error notifications at all. His email address is firstname.lastname@example.org
I've attached a screen shot of his notification settings, and the notification that I received.