two basic decisions damaged Intel's prospects in th cell phone market
(and it was not not lack of resources, because Intel blew off a dozen billions on other two other resource consuming decisions, Macafee and flash).
Anyway, the two early decisions were
1- smart phones will not get a large market quickly
2- whenever Intel decides to enter the smart phone market, customers will be very receptive to it, even if very late.
It would be unfair to fault the management for not predicting the future correctly. However the decision to keep Atom on 45 nm for years, while more advanced process was available was a wrong decision at the time it was made, regardless of how the future would turn out.
But hey, that's how some companies prosper and others do not.