I'm not trying to argue that most people upgrade yearly. I don't have any knowledge or opinion about that. I'm also not saying people only buy iphones for status. I have one myself, for pragmatic reasons. I'm just pointing out that a majority of people owning a particular brand doesn't mean people can't signal status with that brand. They can still do it by owning particular models. You see this all the time with cars. The a new high-end Lexus conveys status even though you see a lot of old beat up Lexuses being driven around by poorer people. The subtle design changes of iphones from year to year, I would argue, are meant to provide that same effect.