It’s mobile prehistory at this point, but there was once a time when the ultimate smartphone you could get was a BlackBerry. Before Apple’s iPhone arrived, Google’s first Android prototypes were basically BlackBerry clones. It’s easy to think of the stratospheric rise of Android and the iPhone over the past few years as inevitable, but we sometimes forget just what outsiders both of these platforms once were. Back in 2006, neither Apple nor Google had established relationships with carriers. Neither had a loyal following of business users to bolster its consumer proposition. And neither had the best text-input method ever devised for a pocketable device. BlackBerry, then known as Research In Motion, did. And it’s partially because of those advantages that BlackBerry is this week shuttering its phone design and manufacturing for good.

The story of BlackBerry’s mobile demise stretches so far back that we wrote a forensic dissection of it back in early 2012. It’s actually to the company’s credit that it managed its crash landing as well and for as long as it has done. BlackBerry persists today and has refashioned itself around its enterprise and software services, which have been propping it up for a while, and doesn’t look to be in danger of following in Nokia or Palm’s ill-fated footsteps.

But the reason why BlackBerry is interesting today is that it provides a prime example of an incumbent business being disrupted by sprightlier newcomers. Success, as BlackBerry had a decade ago, breeds two interrelated negatives: conservatism and complacency.

At the time of the iPhone and Android’s arrival, the whole mobile industry was on the precipice of moving to bigger touchscreen displays. That was the destination that technology was evolving toward, and it was a trend that Apple jumped on with perfect timing, and later companies like HTC and Samsung exploited to the fullest. HTC was never influential enough to unilaterally dictate that screen manufacturers build bigger, and the prime reason for its repeated success at the start of this decade was that it had nothing to lose and just kept moving to the latest spec with the greatest speed. Most Android OEMs, in fact — companies like LG and Sony along with Samsung and HTC — essentially functioned as dumb conduits for the latest specs. Dual-core processors become available and LG was so fast to implement them that it got a Guinness World Record for it (and a bunch of dissatisfied users owing to its buggy performance).

While all the tumult and furious evolution was happening on the Android front, BlackBerry was more concerned with protecting what it already had instead of conquering new lands. It’s understandable. The majority of big businesses and government organizations relied on BlackBerry’s superb security, reliable email, and utilitarian functionality to keep their workers productive on the move. BlackBerry Messenger had even accomplished the unlikely feat of making a business device popular among young users as well. Nokia’s Symbian might have had the biggest share of the global market, but BlackBerry dominated in the United States, which has been the tastemaker for new technology products since forever. It was just a comfortable place to be in.

It’s hard to argue that BlackBerry should have thrown away all the goodwill and loyalty it had accrued with customers and thrown itself into the large-screen smartphone race. The BlackBerry keyboard will remain an iconic part of mobile history precisely because of how effective and popular it was. It’s just that the mobile industry went through a uniquely transformative period of rapid evolution at a time when BlackBerry was best served by making iterative improvements.

But being conservative and seeking to appease existing customers was only half of the problem. BlackBerry also exhibited hubris with disturbing regularity. It launched the PlayBook tablet without an email client on board. It insisted, along with Adobe, that Flash would be the future of rich mobile content, and it delayed the release of a spec-competitive smartphone until it had a chip powerful enough to handle the requirements of Flash. BlackBerry believed people would wait for its superior product or would put up with limitations, because, well, it’s BlackBerry. If that sounds like Apple’s approach with things like the recent headphone jack removal, the big difference is that BlackBerry was selling tens of millions of devices per year at its zenith, whereas Apple now does close to double BlackBerry’s annual tallies each quarter. The latter simply has more latitude to act haughty.

It’s the very definition of complacency to think that you have more room for error than you actually do. And that was BlackBerry, a company that knew it had a lot of assets and advantages, and therefore exhibited a reluctance to embrace change and a consistent smugness about what it had already accomplished. To be fair, most of BlackBerry’s biggest mistakes — things like keeping BBM locked down to its own hardware in a world where the cross-platform WhatsApp grew into a $19 billion business — are historic, but it was as recently as last year that the company’s CEO was showing off a new device without actually being familiar with what it could do, or even what its peculiar name, Priv, is supposed to stand for.

So now, with a quiet whimper of irrelevance, BlackBerry departs the smartphone market that it once helped to shape and define. It's an instructive lesson to any company with less than a billion users of its products or services: no matter how good you may already be, there's always the potential to do better, and if you're not willing to change and do the scary new thing, someone else will. Adapt or die.