If you enable Face ID on iPhone, you can authenticate tasks such as “Unlock iPhone”, “Authenticate Apple Pay”, “Purchase at App Store”, etc. with Face ID instead of “Passcode”.

Play haptics after successful Face ID authentication

iPhone settings

accessibility

Play haptics after successful Face ID authentication

If you don’t need haptics, turn it “off”

Play Haptics on Successful Authentication Play haptics when you successfully unlock your iPhone with Face ID, authenticate Apple Pay, or verify iTunes and App Store purchases.