Add double tap on fingerprint sensor to activate fingerprint sensor when locked.. always on results in too many unnecessary touches and double tap on screen is bit of extra burden on fingers..
Double tap on fingerprint sensor avoids both of them....
Effectively, that could be a good idea, I was using the fingerprint always on on my old device (with side mounted fingerprint sensor) and it was a little bit frustrating that sometimes, when I just wanted see the time, my phone would unlock
