Starts off well, but then collapses into facile and shallow trope "what keeps Apple revenues flowing is just fashion"
But no, fashion is suddenly this incredibly powerful beast (true) that for Apple has become a perennial, because, er, suddenly the theory trips over it's own laces.
For a better insight into one of the main reasons Apple succeed, this article is a good read:
http://rampantinnovation.com/2014/05/13/design-is-about-intent/
In summary Apple have design intent to their core. They avoid falling foul of the three design evasions:
1. The first design evasion "Preserving" - Apple have always been prepared to rip-up the blueprint for a previous design success where their competitors do not. Microsoft clearly have suffered badly from this evasion, and as this The Register article points out, where they have ripped up the blue-print (e.g. Windows phone) the result is much better.
2. Copying - Apple are perfectly prepared to copy but only after they have evaluated it is the best solution. They don't abdicate on the responsibility to place the design effort first and evaluate it is the best solution in the current context. Samsung have too often taken the copy first / think later short-cut. Their shameless equivalent of the Apple passbook is a good example of the level to which they are prepared to go in not thinking for themselves. It is pernicious because it can appear to help the company, but it also places an upper limit on user expectations as to what to expect of that company. It's a bit like saying I'll compromise my reputation to achieve scale. It can be done, but it's an existentially limiting trade to make. In life we all have to decide how we are going to live in that regard. If for example I become a photographer, and want to be taken seriously, I can't make a quick buck by shooting porn, or even doing low value magazines, and hope to easily recover my reputation as a top photographer.
3. Delegating - also pernicious because it dresses in the garb of reasoned scientific method. Microsoft fall foul of this problem (the office ribbon bar being an example). This is where design direction is surrendered to the uncoordinated masses through delegating the process to the results of focus group and user research. The abdicating "designer" always has an excuse to fall back on "our research showed..." Steve Jobs would give the Henry Ford quote to illustrate the problem of this third evasion. "If I had asked people what they wanted, they would have said faster horses."
Apple will fail if they start to diverge from their drive to put design first. Which brings me to their Beats purchase. I've been puzzled by this for some time and concluded Tim Cook had slipped up (I wrote my feelings up here and they seemed to be well received; http://www.theguardian.com/technology/2014/may/09/apple-looks-set-to-buy-dr-dre-beats-electronics#comment-35409955)
However, now I think that conclusion was wrong and it has suddenly clicked. Apple like to own the full stack. The oldest and most low-tech connector on a mobile device these days is the headphone jack. And we are heading for a new level HD audio. Apple like to be thought of as the technology firm who "owns" music.
Given they rarely allow themselves to fall foul of design evasion 1 - I predict they are about to go all in on HD audio. In Apple style they will simply wholly remove the 3.5mm headphone jack from all iOS devices coming out this year and moving forwards. In 2 years it will be near as dammit a forgotten connector. If they do this, there will be one hell of a user base purchasing new speaker/headphone tech with a new connector standard (possibly lightening and/ or a new higher throughput low power wireless standard / upgrade to low-power bluetooth). They have been losing some of their lustre as THE tech music company. By buying Beats, and going all in on HD Audio, they reap the profit from the inevitable Tsunami of consumer upgrade behaviour, and fully establish themselves as design leader amongst their peers.