Dominant Hand
When I was setting up my Apple Watch, I was asked if I was wearing it on my left or right arm; it never mentioned dominance. I wear the watch on my left arm; I'm left handed. I'm sure this skews the data....
Question marked as
Left or right arm, and Digital Crown left or right, simply allow the watch to determine its orientation This puts the screen is the right way up, and sets up functions like Arm Raise to know the correct motions and activate the screen.