During the heydays of the iPod craze, around 2005-2008, I was convinced that product line would be short lived. It was apparent that music playing was a trivial application of mobile phones, which were already becoming ubiquitous. In those days, Nokia was a far bigger cultural phenomenon outside of North America (where Nokia never gained much of a foothold). And it was truly global, not just European: even tiny villages in rural Asia, Africa and South America had Nokia vendors.
So in my straightforward projection, it was only a matter of time before the iPod would be crushed by the likes of Nokia, Sony-Ericsson, Samsung, LG, etc. Never did I imagine that Apple would turn the tables on the phone manufacturers so dramatically after 2008...