It's often said that Apple is sitting on too large a horde of cash, that if it can't come up with ways to deploy that cash that exceed its own internal rates of return or other such hurdles (to use finance speak), it should return that cash to shareholders.

On Quora, an anonymous account posted an interesting take on why Apple accumulates so much cash and how it deploys that as a strategic weapon.

When new component technologies (touchscreens, chips, LED displays) first come out, they are very expensive to produce, and building a factory that can produce them in mass quantities is even more expensive. Oftentimes, the upfront capital expenditure can be so huge and the margins are small enough (and shrink over time as the component is rapidly commoditized) that the companies who would build these factories cannot raise sufficient investment capital to cover the costs.
What Apple does is use its cash hoard to pay for the construction cost (or a significant fraction of it) of the factory in exchange for exclusive rights to the output production of the factory for a set period of time (maybe 6 - 36 months), and then for a discounted rate afterwards. This yields two advantages:
Apple has access to new component technology months or years before its rivals. This allows it to release groundbreaking products that are actually impossible to duplicate. Remember how for up to a year or so after the introduction of the iPhone, none of the would-be iPhone clones could even get a capacitive touchscreen to work as well as the iPhone's? It wasn't just the software - Apple simply has access to new components earlier, before anyone else in the world can gain access to it in mass quantities to make a consumer device. One extraordinary example of this is the aluminum machining technology used to make Apple's laptops - this remains a trade secret that Apple continues to have exclusive access to and allows them to make laptops with (for now) unsurpassed strength and lightness.
Eventually its competitors catch up in component production technology, but by then Apple has their arrangement in place whereby it can source those parts at a lower cost due to the discounted rate they have negotiated with the (now) most-experienced and skilled provider of those parts - who has probably also brought his production costs down too. This discount is also potentially subsidized by its competitors buying those same parts from that provider - the part is now commoditized so the factory is allowed to produce them for all buyers, but Apple gets special pricing.

For me this recalls sushi restaurants. When I first graduated college and finally had enough money to eat sushi regularly, I'd sit at the bar at a sushi restaurant and watch the sushi chef cutting the fish and wonder what was so difficult about what they were doing. After watching a few of them, I felt like I could climb over the counter and assemble a reasonably good piece of sushi myself.

After watching Jiro Dreams of Sushi, I realized that watching a chef prepare a piece of sushi was just the tip of the iceberg, that much of what set one sushi restaurant apart from another was the supply chain, the relationships with the right buyers and suppliers and fishmongers that helped secure the best ingredients.

This strikes me as the same way most people underestimate Apple. They see the aesthetics of the final product, the software or hardware design of an iPhone or a MacBook air, and they don't see any sustainable competitive advantage. All of that can be copied, they think.

Leaving aside the fact that in hardware design if you have to copy someone else in technology you're already one generation behind, what people often fail to see (or can't, given Apple's secrecy) is the massive supply chain edifice below the water's surface. Scaling in software may be less of a problem for David than it once was, but in hardware it pays to be Goliath.