I was having lunch recently with a friend who runs an Apple-oriented software developer firm. He was curious about my take on Windows 8 and Windows Phone, and how Microsoft's latest platforms would fare in the coming year. "What's interesting," I said, "is that Windows 8 is actually more controversial than Windows Phone. Sure, Microsoft's smartphone platform isn't selling well, but the consensus seems to be that the company was right to start over from scratch and that – go figure – the platform itself is actually very solid."

"No matter how successful Windows 8 is for Microsoft," I said, "it will mark a major shift for the software giant. And this shift will have enormous repercussions on its customers and on the tech industry."

It sounds obvious enough. But what do I mean by this?

Let's say Windows 8 is enormously popular, a Windows 7–level success story with customers. In this scenario, consumers have embraced ARM-based, iPad-like Windows 8 tablets over competing tablets and businesses have embraced a mix of more traditional Windows 8 PCs. That is, Windows 8 isn't just a platform for PCs, it's a platform a new generation of devices as well. Growth ensues.

But let's say Windows 8 flops with consumers on tablets. Yes, many still buy traditional PCs, because that's what they know. Businesses still buy Windows PCs, too, for similar reasons and because they are highly manageable and compatible. But the market for traditional PCs will eventually slow, flat-line, and then decline. And the market for non-traditional computing devices, such as tablets and smartphones, will continue skyrocketing. At some point, PCs run the risk of becoming the bottom of the market, not just in revenues, but in sales. Most people will engage in computing activities on other types of devices.

In the former scenario, Microsoft plays a major role, because it will own a platform that runs on all the major device types. Even in this best-case situation, however, Microsoft is no longer the dominant technology player it once was, as the world becomes more heterogeneous. But it plays a major role and can still grow going forward because the market is also growing.

In the latter scenario, chain reactions ensue. Microsoft gets locked out of this future market for computing, at least from a platforms perspective. And that means the company stops growing as it controls an ever-shrinking part of the market. Further, the company would have to change yet again, and there are only two obvious paths: It can choose to serve the business market only, or it can return to its roots as an applications maker and target all of the major mobile platforms – primarily Android and iOS – with its most popular applications and services (e.g., Office).

At this point, I was interrupted by an incredulous outburst from my lunch mate: "Do you really believe this?"

I do. As I keep pointing out, the risky thing here is that there is a coming generation of computing consumers who aren't growing up on Windows and Office, and they won't demand access to these tools when they enter the workforce. And it won't be because they feel strongly about it. It will be because they just don't care.

As the world turns inexorably toward cloud-computing services and to proprietary mobile apps, Microsoft is busy creating a new version of one of its most venerable products, one that – not coincidentally – emulates the mobile app experience, connecting to cloud services fairly seamlessly. But this could very well be a situation like that occurring now with Windows Phone. On that platform, Microsoft has done a stellar job of creating something unique, innovative, and efficient, and the company has courted developers to great success. No one, however, is buying the product.

And then I asked my friend a question of my own – one that's been eating away at me lately: What if this happens to Windows 8?

There hasn't been much talk about this yet, because the reactions are fairly predictable, but I see Windows 8 as Microsoft's Hail Mary pass. If Windows 8 doesn't truly succeed (i.e., it achieves just Vista-level sales and customer engagement), the company might never fully recover. The failure of Windows Vista already knocked the stuffing out of Microsoft, leading to the complete upheaval of the Windows Division, and here they are making a big bet again, far earlier than I ever thought was possible. What if this one doesn't work? What if users don't embrace this weird dual-usage model with both tablet-friendly and traditional UIs? What if the world just passes them by?

I assume there are bigger brains than mine mulling this over right now in Redmond. I assume people are losing sleep over this. But I go out into the world and I see people using MacBooks and Gmail and Amazon.com and I worry that this is a peek into the future. I worry because I don't see Microsoft prepared for that possibility. Yes, by all means, improve Windows, and make a play for this future. But what's Plan B?

IT pros should be worried too, because this won't affect only the consumer market. In businesses, I see nothing but fear in the face of cloud computing, because many of these hosted services are in the process of permanently reworking the mix of jobs that are available within companies all around the world. But the changes wrought by cloud computing will seem like the good old days if Microsoft falls apart and its familiar software and services, and all the manageability that comes with it, go by the wayside.

This is the type of end game that you'd think would excite anyone on the Apple side of the fence. But an odd silence descended over the table as we both considered these possibilities. Presumably, my friend was expecting at least some kind of partisan bravado.

"I don't like it," he finally said. Right. I don't like it either.

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