It may work most of the time. Until it doesn’t. Without any chance to understand why. Your users will blame you and I don’t blame them.
With this issue I used to just worry about my friends shipping their apps. Now I worry about the entire ecosystem. Mobile apps require syncing.
There are three things Apple could have done:
Not provided a syncing system.
Provided a syncing system.
Provided a syncing system that doesn’t work.
Of all the options, #3 is the worst, because it leads developers down a bad path, and because it makes users expect developers to use that syncing system.