Once in a blue moon, my phone goes into this dark place where no matter what I do, it always locks itself about 1-2 seconds after pressing the unlock button, before I have a chance to enter a pattern to unlock it, rendering it completely unusable. This condition persists after restarting and removing the battery. It's an LG Escape 2 with KitKat. My sister has told me she has this problem too (she has the same phone and service provider from the same store), though nobody else in the world seems to have this problem to my knowledge, so I imagine it's a unique combination of hardware and software.
And since the spam filters on this website are so clever, let it be known that I have a video to demonstrate this problem at the following URL:
[some website] /
I would appreciate it if someone would help, because although I appreciate all my phone does for me, I would rather not have it turn into a brick on occasion.