Downswing graphs usually have the EV line in part because the poster wants to show that it's just bad luck and not bad play on their part.
Upswing graphs usually don't have an EV because the poster would rather not show that an upswing was due to running above the EV line for obvious ego related reasons. 
Hopefully, we'll get enough +EV graphs to balance out all the -EV ones seen all over this board.
Thx.
