Kicking (ahem) things off, here’s Dieter Bohn on the above situation:
It’s a distressing thing to discover just two days after receiving my review unit. More distressing is that the bulge eventually pressed sharply enough into the screen to break it. You can see the telltale lines of a broken OLED converging on the spot where the bulge is.
Whatever happened, it certainly wasn’t because I have treated this phone badly. I’ve done normal phone stuff, like opening and closing the hinge and putting it in my pocket. We did stick a tiny piece of molding clay on the back of the phone yesterday to prop it up for a video shoot, which is something we do in every phone video shoot. So perhaps a tiny piece of that snuck into a gap on the back of the hinge and then around or through its cogs until it lodged in between the screen and the hinge. It’d be sort of like Charlie Chaplin getting caught in the gears in Modern Times.