I don't know why iOS 8 adoption has slowed

On Monday, several sites picked up on a dramatic slow down in iOS 8 adoption. It didn't take long for speculative headlines to follow. Many stated that iOS 8 bugs caused customers to hesitate, such as this headline from The New York Times:  

'Apple’s iOS 8, After a Buggy Start, Is Adopted More Slowly by Customers'

John Gruber called the stall "Very worrisome - a canary-in-the-coal-mine indicator that casual users no longer trust Apple with major iOS updates." John has since updated his thoughts on the matter, joining what many others believe is the root cause - the 5 GB of free storage space required for the over-the-air update. I don't doubt that this is part of the issue (it was something that I had to work around in my household).

But this 5 GB requirement is only 2 GB more than the 3 GB iOS 7 required. Its adoption rate was called the fastest software upgrade in history reaching 64% a month after its release. While the extra 2 GB is likely a significant upgrade deterrent for many, my gut tells me there is more to the story.

So why the dramatic slow down in iOS 8 adoption? I have some ideas, but I really don't know.