The only times Arch broke for me were when I broke it. There were 2 exceptions, however.

1. I once went a long time (a few weeks) without updating and I had issues relating to keys and the pacman keyring. Luckily, Erik Dubois had a video about exactly that and the system was fixed within <30 minutes (including finding the video and watching it)

2. The other time my computer turned off during an update which involved updating the kernel so my system broke (I can't remember if I turned it off or if it ran out of battery). I recovered it using live media, chrooting and doing an update again from inside the chroot, which fixed it. Once again, took about 30 mins.

Every other case of breakage was caused by me actively tinkering with the system.

I should note that this doesn't include minor issues like some configuration no longer working because of an update or something like that, as 1. this isn't a system-level breakage and 2. it isn't Arch's fault.