I don't think anyone would go over every line in the kernel source before updating their kernel, that'd be nuts. I also don't think they'd audit every line of code on their machine.

The business world is different than the real world though, Microsoft sludge is an acceptable risk because it's by far the standard across the board. I don't like it, I'd love a Linux desktop, but I don't get paid to like things.

The biggest disruptions I've seen in the past year were caused by people with a sense of entitlement. Everyone's human and makes mistakes, even if you're a level 80 paladin with a flying mount at night.