The Galaxy S8’s fingerprint sensor may not be in the most ideal location on the back of the phone next to the rear camera lens. But if you bought a Galaxy S8 you’ll still want to set up that sensor to recognize one (or more) of your fingerprints.
Not only is a fingerprint a more secure way of unlocking your phone than with a PIN or swipe pattern, it's faster, too. And setting up the fingerprint sensor allows you to do things like confirm mobile payments with your S8 or use the Secure Folder feature.