Which affect the OS mostly and not individual apps. Funnily enough OS updates are usually not automatic. Which I think is a good thing because vendors keep mixing them with "feature updates" which end up making things worse (looking at you Samsung).
I'd love for Google to take away the security update channel from the phone vendors and auto-update ONLY security-related things through that.
The early adopters. There are always people that will weight that risk of latest & greatest and vs buggy differently, it should be a choice. Especially for apps that don't have a beta testing or early bird channel.