The other day, my father asked me a question about his laptop. I marveled as he handed it over: a 2008 aluminum MacBook (the bizarre one-off model that lacked a FireWire port). Even after seven years, this hunk of metal and glass was going strong. Sure, I put in a new battery and replaced the hard drive with a solid state model, but the bulk of the machine is unchanged, and it reminded me of something that I don't think Apple gets enough credit for: product longevity.

If it ain't broke

It's an old chestnut in the Mac community that Apple's computers have longer lifespans than Windows PCs, but in recent years, it's become even more apparent that Apple wants to keep its products sustainable in the long run. If you look at the system requirements for the upcoming OS X El Capitan, for example, you'll see that it'll run on computers as old as a mid--2007 iMac. More to the point, you'll notice that those requirements are unchanged from its predecessor, Yosemite. Which were unchanged from its predecessor, Mavericks. And from its predecessor, Mountain Lion. And so on. In truth, Apple's base requirements for OS X haven't much changed in at least five years.

Perhaps more impressively, system requirements haven't changed much on the iOS side either, despite the rapid iteration and development in the smartphone realm. The forthcoming iOS 9 will work on devices as old as 2011's iPhone 4s and iPad 2. (Of course, whether it will run well on those devices is always a question.)

Both of those are feats of engineering, but at first blush they also seem somewhat counterproductive. After all, Apple makes money when customers buy new devices--if their seven-year-old computers continue to run the latest and greatest operating systems, what's the incentive to upgrade?

Well, better performance, of course. And newer, shinier features. While those operating systems may run on every piece of hardware dating back to the recession, the hardware's not present for the support of some features: Handoff, for example, requires a specific wireless chipset. And older devices don't meet the latest and greatest Wi-Fi standards.

But whereas it sometimes feels like the rug is being pulled out from under us as technology consumers--oh, sorry, that model isn't supported anymore...have you considered buying this new one?--Apple's approach to upgrading is more carrot than stick. Enticing us to buy a new device without taking the mob-enforcer-style approach of busting the kneecaps on our current machine.

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Good for you, good for me, good for America

You could make the argument--were you cynically inclined--that maintaining a longer list of compatible devices actually helps Apple incite customers to upgrade, since it ends up with users stuck between the rock of not having the latest features and the hard place of having a device with subpar performance.

Personally, though, I take the other perspective: by supporting older devices, Apple's living up to its own self-proclaimed goal of pleasing its customers. Nobody likes to feel that they have to ditch their computer just to upgrade to the latest software.

It also happens to work to Apple's benefit, because establishing less fragmentation of operating systems makes the features the company does roll out more compelling. We think about this more on iOS, which Apple has regularly upgraded, but it's true of OS X too. By enabling more users to adopt the latest operating systems, developers--Apple included--can target their software towards the newer platforms with less fear of leaving older hardware behind. It's also a big chunk of the reason why Apple offers its major software releases for free.

There's also an element of safety: by maintaining current software on older platforms, Apple can also ensure that the latest patches to security vulnerabilities are rolled out to all of the machines that might still be in use. By comparison, look no further than the recent high profile vulnerability that hit Android devices to see the effects of widespread platform fragmentation.

Keeps on giving

This longevity goes hand in hand with the decline in specs that I wrote about last month. We'll continue to use our devices as long as they accomplish what we want them to, not simply when specs suggest we "should" upgrade.

So I think of my dad, working away on his 2008 MacBook. Ultimately, if Apple continues at the pace that it's at today, that computer's useful life could extend to a decade from its purchase, which is a pretty outstanding return on investment. Granted, he mainly uses his machine for web browsing and email reading, tasks that aren't exactly taxing even to a seven-year-old machine.

Meanwhile, those of us who do upgrade to get that new, shiny product--like me, who's gone through seven smartphones in eight years--can still turn around and sell our still-perfectly-functional older devices to a vibrant secondary market, where they'll hopefully continue to work for years to come. And that's good for us, good for the people who buy them, and even good for Apple.