Apple's entire business is based on breaking new ground with an innovative new product, exploiting that products uniqueness before the rest start copying them and flood the market with "me too" devices. Then Apple has to move on to something else.
Which is why they've stopped making iPhones now that the market is flooded with cheap Android devi... oh, wait, they didn't.
Apple continues to improve its products, and it also makes fairly high quality stuff. My next desktop computer will be a Mac in part because I happen to prefer OS X over the abomination that is windows and the amateurish copycat that is the Linux desktop (not talking about servers here, all my servers run Linux), but also because of all the desktop computers I've ever owned, only my old C64 was more reliable and lasted longer.
This "running to stand still" existence cannot go on indefinitely.
Why not? Whether or not its true, there are other companies and even entire industries that work the same way, for example the fashion industry, and plenty of people have had a lifetime of employment from that.