I haven't had Arch break during an update, but I always check the home page first, there are absolutely times my system would have broken during a blind update.

Arch doesn't support blind updates - it explicitly tells you to always check the home page before an update in case "out-of-the-ordinary" user intervention is required. https://wiki.archlinux.org/title/System_maintenance

Basically, don't run arch unless you're willing to be a Linux system admin.

Stable doesn't mean that the OS doesn't break, but that the way it functions doesn't change.

I see. I asked because "stable" means different things in different distros. In Debian it means that interfaces and functionality in one version doesn't change. If I set up a script that interacts with the system in various ways, parsing output, using certain binaries in certain ways etc, I should be able to trust that it works the same year after year with upgrades within the same release. To some people this is important, to some people it isn't.