Having dealt with all new engagements in a stream, when we return to it later we still see everything in there.
It's difficult to keep track of what we've dealt with and what still needs action, and we seem to be wasting lots of time scrolling through previous conversations to check if a new comment has been added at the bottom.
It would be great if, as natively with Facebook for example, once you've dealt with a comment you tick to say 'done' and it disappears from the screen - ultimately being able to achieve Inbox Zero (the dream!)