Although it is rare, there have been certain cases with iOS releases wherein a few devices have been locked or messed up if a specific set of circumstances occur. These occurrences would be rare, but I prefer others to find that rather than me! I also ran into a strange situation with the release of 10.0 or 10.1 wherein there were specific issues with certain iPhone models that were on the T-Mobile system. I even got an urgent email from T-Mobile asking me to wait before installing, followed up a day later by an all is clear email saying it was now safe to install the update. So stuff can happen, and if it takes your device out of service for a day or more that can be very frustrating, especially if it is your only phone. So like many others I prefer for all the gremlins to come out first, then I will update.

I'm still running El Capitan so I'm not concerned about Sierra. The Mac OS X updates are not crammed down our throats like the iOS updates. But I guarantee that Apple will be just as annoying as ever trying to force us to update to iOS 10.3.