Very worrisome — a canary-in-the-coal-mine indicator that casual users no longer trust Apple with major iOS updates.

It’s not that they don’t want.

95% of users don’t get the important changes of the new OS at all, which mainly affect app developers.

Incidentally, iOS users were probably more reluctant to upgrade from 6.0 to 7.0 because of the whole UI change (which wasn’t liked, to say the least).

And 7.0 was way more buggy and slow than 8.0 was.

It’s because they can’t.

iOS 8 requires a lot of free space to be installed, and this free space is simply not available. Users don’t know how to and/or don’t want to delete apps and media for a minor advantage in their view.