Case: My wrist wearable seems to vibrate more often than I would like.
Things to try:
1. If your wearable is displaying the time and date, tap on the circle once to get to the heart monitoring screen.
2. When you see the heart in the box and the number next to it, heart rate is being monitored and a vibration will occur every few minutes.
3. By holding your finger on the round circle on the right for a few seconds you can turn the heart monitoring off.
4. When Heart Rate monitoring is off, you will see the word "OFF" next to the heart icon.
Reference Images from device manual and device interfaces: