This is wrong. Build numbers are same but IPSW filesizes are different.No need for that.
If you're on 14B72c (on a 7/7+) or on 14B72 (on all other devices) you already have the final version.
It's been different for different updates and even different devices over the last few iOS versions. Sometimes people get welcome screens, other times they don't, sometimes they get delta updates, sometimes they don't. It's certainly has been somewhat more out there with iOS 10 and iOS 9 in some sense, but it was also happening with iOS 8 to some degree as well as I recall from some threads.I honestly cannot remember. Is it usually for .0->.1 updates to be delta and not full installer? I didn't even get the Set Up Screen. Again, nothing surprises me anymore. 2016 has been the weirdest year for updates.