Saturation and people are satisfied with what they have.
Take my mother-in-law (please) for example. She does _everything_ on her iPad. Banking, email, surfing the web. She literally (yes, literally) hasn't touched her desktop computer in years.
But, she's still only on an iPad 2. She'll run that into the ground before she'll get another. She loves it, but isn't on any "upgrade cycle", the same for many people.
Now, it would be different if iPad sales were down 18%, yet Android or Windows tablet sales were rising to fill in that gap. As it is, _all_ tablet sales are down.
Take my mother-in-law (please) for example. She does _everything_ on her iPad. Banking, email, surfing the web. She literally (yes, literally) hasn't touched her desktop computer in years.
But, she's still only on an iPad 2. She'll run that into the ground before she'll get another. She loves it, but isn't on any "upgrade cycle", the same for many people.
Now, it would be different if iPad sales were down 18%, yet Android or Windows tablet sales were rising to fill in that gap. As it is, _all_ tablet sales are down.