"Conversely, if Face ID fails to recognize you, but the match quality is higher than a certain threshold and you immediately follow the failure by entering your passcode, Face ID takes another capture and augments its enrolled Face ID data with the newly calculated mathematical representation." source: https://images.apple.com/business/docs/FaceID_Security_Guide.pdf basically: If Face ID doesn’t recognize your face, don’t reposition your face so it will accept it. Instead, type in the passcode so it will add that position of your face to the accepted data set. AWESOME!!