It can help you differentiate between whether it register a quick tap on the touch screen vs a force press.
Not that they do it on the watch, but it could also have a ratcheting-type feel when you scroll to indicate a) that you're scrolling or b) how fast you're scrolling.
The Steam Controller actually used this to great effect.
Oh, I get that it can help. I actually really like the feature. What I didn't get, was how it could help you use it without looking. Touchscreens require you to know what is on the screen, pretty much period. Right?
Ever want to skip a song on your iphone while driving? You know basically where the buttons are, but not exactly and since there is no feedback you cant tell if you are hitting a button, or just empty screen. With feedback you could allow the user to drag their finger around until they located a button based on the feedback.
Not to denounce the tech but if the song skips I can be fairly confident I was accurate. Dragging my finger blindly around seems likely to have adverse effects.
