Apple needs to take the "Yellow Cab" mentality. Yellow Cab kept the same vehicle design for decades, woking out the bugs until the vehicle was basically bullet proof. So, instead of coming out with a new iOS, why not completely fix it prior to moving on with a new one? Has any of their iOS's ever had a version where they got rid of all the bugs before releasing a new one?
It is impossible to deliver complex s/w that has no bugs, it is impossible to prove there are no bugs in complex s/w. they have to update the s/w to adapt to new h/w and to add functionality to stay in the marketplace. You fundamentally do not understand s/w development.