Give Haptic Feedback From Digital Crown
The Digital Crown is how you scroll through items on the Apple Watch. It's been around since the first model, and it's better than scrolling on the small screen with your finger.
With the Apple Watch Series 4, you will feel small vibrations on the Digital Crown as you move across the different options.
This is called Haptic Feedback, and it's similar to the small ticks you feel when the iPhone vibrates as you make different on screen selections and scroll through various options.