Only AUR packages break because of either bad maintenance or bad timing when dependencies get updated but not the AUR package. Other than that I never got any reliability issue, I don’t get all the complaints about Arch being unreliable. Sure, I wouldn’t put it on a server or something that needs to always work the same way and that needs lots of uptime (but some people do it anyways because they like to live on the edge,) but it’s not as bad as people say.