>>368921387
No UI helps a lot to keep things uncluttered. Working with your body to do complex actions rather than searching a keyboard for the right key to press also does. Another interesting thing that makes things easy to track is that your eyes struggle to make smooth movements but can lock on to something and move smoothly in opposition to your head movements. Try it yourself slowly look left and right with just moving your eyes and you'll notice your eyes just flick from point to point. But then if you focus on one spot and move your head left and right your eyes can smoothly rotate to stay looking at something. Moving your head as the camera allows your eyes to properly smoothly track things like this without going out of focus.