Well smart phone is now a trending thing in the modern world. Some people tend to rank them self amongst their peers using the lastest smart phones they bought and since it's very expensive, they gain more like a respect from others. I just wanted to say that you should only speak for your self though. Theses companies produces these phones due many consumers requests and taste. If you take a look at the first iphone, it's size and function back then very was small and not having more features compared to the lastest phones we can see today. If there wasn't a chase for an upgrade then maybe those phones will still be in play.
The truth is as the world is growing, new technology will be designed and old ones will be forgotten. The mass wants something new so these companies will have no choice but to give them their best.