I have a two year rotation.
The cost of the phone to me is $50/year, when buying the most expensive phone.
Assuming, $399, until this year. After two years, selling it for $300, unlocked.
This year, my "for sale phone" has a brand new battery. Thanks Apple.
Additionally, for the passed 5 years, I put all my birthday money towards the new phone. It pays to have a summer birthday.
My total out of pocket expenses, nets $0, counting birthday money... If I stop the cycle, I might end up paying more, which I don't really want to do. What I mean by this, the return of investment covers much of the cost of the new phone. The longer I wait, the lower the return. So the pain is felt the next time I buy a new phone.
I don't know how the new price is going to factor. I may end not being able to recoup the costs after 2 years. ($499) I am worried, the 128GB will still be worth $300 after two years, which sucks.
Additionally, if I don't buy a phone, every two years, I am paying for the subsidy, for nothing. (two lines, means every year, interleaved)
My wife and I have been using the iPhone since the First Gen. I give her my year old phone. She is perfectly happy with this situation. She gets a "newish" phone every year, and I get the "untested" model.
I already have people asking me about my 2 year old phone for sale.
I have to wait until the 14th before I unlock it. But then I can take it (64GB - iPhone 5 - White) and sell it for going market prices. I think $300 is more than fare.
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Ever since the iPhone came out, I have not upgraded my personal desktop computer ONCE.
It doesn't hurt that my 2006 PC is a quad core - ATI HD 2600 XT setup. But still I would have some pretty awesome setup today, if I didn't play the annual iPhone purchase plan.
lol... Not missing it.