We probably have different definitions for "works perfectly fine"
Yes, perhaps we do.
There isn't a phone in the world that has 100% success rate with scanning your fingerprint. Even when the Note 5 came out, there were people complaining. There still are. My phone will unlock, I would say, 95% of the time, first try. A lot also depends on the Home button being clean as well as my fingers. The way I register my fingers is that I do it very lightly at varying angles. Very lightly means barely touching the sensor. I feel that if you don't do this and register with any kind of pressure, then you're going to have to unlock with that same pressure. If you register too heavily, then perhaps the prints distort and if you don't unlock with the same distortion, then the phone won't unlock. Try registering very lightly, then unlock with the same light pressure. Also, if you have a case on the phone, you have to register when the case is on. If you register outside the case and then put the phone in the case, the angle your finger hits the scanner may change and the phone may have a hard time unlocking.
Here's a very boring video I just created of how my phone unlocks for me. Note that there are 25 attempts total and I stopped on the 25 (fail). Before the 25 attempt (fail), the phone failed to unlock 1 time out of 24 attempts (on the 8th attempt)... this is a success rate of 96%. I didn't plan this and there's no way to fake it either. I also didn't count the attempts while I was doing this, so I had no idea what the percentage would turn out to be. One thing to note is that the phone isn't even in the position I normally hold the phone at... there's a camera I had to reach around to make the video. And yes, it was uncomfortable!
Yes, many people grumble about the scanner, and when I say I don't have a problem with it, they are highly skeptical. But I really don't have any problems with it... I also don't expect it to work 100%... thus, the scanner works perfectly fine for me!
https://forums.androidcentral.com/e...%3A%2F%2Fvimeo.com%2F164635950&token=imUkZMxl
Sorry for the boring vid, but there's only so much you can do to demonstrate unlocking a phone. By the way, the other video on my channel is about how I see minimal lag from camera to gallery. Many people grumble about camera to gallery lag being excessive. I don't see it.