At some point you have to trust *someone*.
Do you drive a car? You have to trust that someone driving towards you isn't going to swerve over and hit you. It would be easy to do.
Do you walk on a sidewalk? Same thing...
Apple has screwed up updates a few times, but you have to, I have to, trust that they are doing their job well because I can't do that job myself. That goes for everything of a technological nature. I can't write firmare for a Cisco firewall, I just have to assume that they have done a good job trying to protect their customers, and me. It's not like clothes, where I could, say, make my next pair of pants, or fix a hole, or tear. The iPhone and iOS are easy to use, and provide a lot of flexibility to do the things I want to do. I have to trust them, and so many other entities and such all throughout my existence. Things, for the most part, seem to be managed fairly well. Planes don't fall out of the sky (all that much), cars get from point a to b, the TV works (usually), and the beer is cold. Existence is fraught with enough drama and stress. You have to trust, have faith, or go off the grid? I mean, *someone* could be watching me type this right now, and laughing at the reactions (if any), but I hope they are having fun, and they should remember that someone is very likely also watching them!