This only happens if the face is deemed similar enough to the original face data, which is unlikely if it's a completely different person. Here's the entire qu

This only happens if the face is deemed similar enough to the original face data, which is unlikely if it's a completely different person. Here's the entire quote: "…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"