I have noticed and confirmed on several occasions when the emails are sent, the screen which displays sent, opened, delivered etc. is incorrect.
It indicates that emails have been delivered when actually they were not. My suggestion is that that number is made to confirm the exact amount delivered when they are. Having it the way it is now makes us not know when our campaigns actually reach who we want them to. So if we want to follow up with a telephone call for instance, the client in actuality has not even received the email yet. I would like to see this somehow rectified to be more accurate.