When viewing the Inbox, the order is newest to oldest, from top to bottom. This makes sense. (Screenshot 1-Inbox.png)
After clicking on a notification, it opens a view that shows all activity of the task in the same order, newest-to-oldest, top-to-bottom. This is where the confusion occurs. On top of this, if you open a thread in this view, the order of those messages is actually oldest-to-newest, from top to bottom. (Screenshot 2-Notification Details.png)
When viewing a task in the dialog, the order of the activity is oldest-to-newest, from top to bottom. This makes sense. (Screenshot 3-Task Activity Panel.png)
I always have to click through, past the intermediate screen to get to the task because it is easier than shifting the order in my head that the activity on the task is being displayed. To highlight, the order on the Inbox screen itself is fine. It is specifically that intermediate page that throws me off.