There are two reasons why you may need to erase data and reset your Apple Watch: a technical problem or selling and exchanging the watch. If your Apple Watch is facing a technical problem, resetting it is the last solution you should try. In these cases, if the problem is with the clock software, the problem will most likely be solved.
Also, if you plan to sell or trade in your Apple Watch, you should reset the watch to ensure that no one else has access to the private data stored on it.
When you erase content and settings on Apple Watch, the device completely erases photos, contacts, music, and apps, and turns off other services like iCloud, iMessage, and FaceTime. So, make sure you have backed up important Apple Watch data; Because when you erase the device data, the content is not deleted from iCloud.
Not to mention that things like iPhone Bluetooth pairing and credit or debit cards set up with Apple Pay on Apple Watch and Apple Watch passcode must be manually configured or re-added and cannot be restored by Backup.
Methods of erasing Apple Watch data
To erase all the data on the Apple Watch, you can use the watch itself or the iPhone.
Clear Apple Watch data through the watch itself
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