if you open your F3 in gamemode 3 and enter an entity, your coords on x,y,z WILL change. but the facing (West, Towards Negative X)
will not change depending your facing
(tested in minecart)
see attachment for more info
first pic facing west
sec pic facing south (west is at the right -->)
third pic facing north (<-- west is at the left)
still giving (West, Towards Negative X)
This ticket has been marked as a duplicate of MC-46751, in favor of the more general or better information provided.