The sequence of posts in a thread, as it is now presented, has the first reply at the bottom, and the newest one just below the original post (OP). This is very unnatural, especially when there are many long replies in a thread.
Many of the replies comment on or contradict a previous reply. With the present arrangment, it is difficult to follow the way the discussion is going.
To follow a thread, one has to read the OP, then scroll down to the top of the bottom message. If the message is too long to fit on the screen, we have to scroll down to read the whole message; then jump upwards to the top of the next reply, scroll down again to read the whole message; then jump upwards again to the top of the next message, scroll down again to read it; and so on and on.....
It will be much easier to follow a thread if it is arranged like this -
Original post
Reply #1
Reply #2
Reply #3
Reply #4
....
....
This way, only a downward, progressive scrolling is needed to read the whole thread. It is much more natural. Please change the present arrangement, eBay.