One thing that's created an annoying unexpected problem for me is a message I keep getting on all my Apple devices that I have to reset Keychain. I've had to sign in multiple time to get it going. All because I signed out of icloud to create an Apple ID for my wife. When I signed back in, it wanted me to type in the passcode from another device, which I could figure out. Because I could do that, all hell has broken loose.