Four months ago, Microsoft released Windows 8, a complete rethinking of the interaction between humans and computers. As a paradigm shift, the only real comparison is when Apple introduced the iPhone, moving the world from clunky Soviet-style mobile interfaces to the colorful, responsive touchscreens we have today. Of course, Apple had the advantage of not having to support 20 years of legacy code. Today, Microsoft isn't so lucky. Many programs designed for Windows 3.1 (released in 1992) will actually run on Windows 8. This is an astonishing feat of engineering, but also a giant boulder that Microsoft feels compelled to push up a hill. And such robust backward compatibility comes at a price. The biggest problem with Windows 8 is every version of Windows that came before it.

To understand why Microsoft is all but required to support programs written when Bill Clinton was an obscure southern governor, you have to look at the Redmond company's install base. Microsoft's Business division is worth $24 billion, and the Server and Tools division brings in $18.7 billion. Those two divisions represent more than half of Microsoft's total revenue — almost all of it from corporate America. (And those numbers don't even include Windows dollars.) Steve Ballmer, CEO of Microsoft, has boasted that there are 670 million computers running Windows 7, and every one of them is a potential Windows 8 upgrade.

But they're not, really, because the vast majority of those systems do not belong to your average consumer. They belong to rigorously controlled corporate IT departments, the members of which are obliged to keep business systems up and operational at all times. This leads to massive testing delays across the board. You don't just upgrade to Internet Explorer 8, for example, as such an upgrade might break a database developed in Visual FoxPro that cost $80,000 to build and brings in revenues of $2 million. Carried forward, by the time the largest of corporations with the most workstations and custom internal software gets around to parting with Windows 7, Microsoft could well be on Windows 10. 

Microsoft can't move much faster than the IT departments of their enterprise install base, but Microsoft needs a fast adoption of the new Windows interface, and they need it now. Microsoft engineers must feel like velociraptors handcuffed to brontosauruses. As a way of assuaging corporate IT trepidation, Microsoft strives for backward compatibility, whereby the most radically modern operating system in the world can to some extent run software originally developed to fit on a 5.25-inch floppy disk. And yet that is only half the problem. IT managers also hate change because change can be confusing to a nontechnical workforce. Even the tiniest of variations in one version of Windows to the next will always bewilder some non-trivial percentage of users. Why should a shop welder, for example, who uses his computer to pull up photos from an Access 2007 database inclusively, concern himself with skeuomorphism or SMB management? Unlike most IT departments, the guys who work in the trenches are a business's actual profit centers. (When Windows 7 dropped the word "start" from the start menu icon, who can say how many man-decades of productivity were lost?) 

And yet that is one reason why Windows 8 is such a bold business gambit. Since Windows XP, Microsoft has known that a massive overhaul was due. The desktop metaphor was reaching its natural limit, and home users were shifting by the millions toward a simplified (and more secure) walled app model of software. In an attempt to split the baby, Microsoft first tried to add luster to Windows XP through the aero theme, and an oppressive User Access Control to software execution. That abomination was called Windows Vista, and had the opposite effect of what was intended. Aero was garish by and large, when it happened to run on the rare computer packing adequate hardware. Meanwhile, the internet filled with guides to disabling User Access Control entirely, leaving systems more widely insecure than ever before. (This type of problem also appears in password requirements. While P@S$w0rd123 is certainly more secure than January2001, users end up writing down P@S$w0rd123 on a sticky note affixed to their monitor. January2001 remains safely stored inside a human brain.)

By embracing Modern UI, as the swinging slabs of the Windows 8 interface are called, Microsoft is outright telling both the public and enterprise that now is the time to retrain workers and to embrace and roll out the new Windows, because this is the future and there's no going back. And yet the house that Gates built is terrified of severing all ties to the past. Would businesses even consider brand loyalty when faced with the mandate of complete software redevelopment and deployment? Faced with such massive and expensive demands on in-house and contract developers, why not take a hard look at Apple, with their astonishingly well-engineered hardware and rock solid NeXT STEP foundation? 

That is not a door that Microsoft wants to open. Accordingly, legacy software support isn't going anywhere for quite some time. That's why Modern UI is saddled with an anemic and occasionally accessed Desktop interface. As long as both incompatible and contradictory interfaces exist on the same machine, Windows will remain a vaguely schizophrenic experience, and corporate IT will stick to developing what it knows. So how can Microsoft nail the landing of its Great Leap Forward? By showing developers and the IT industry how it's really done. They need to spark imaginations by demonstrating to the world the most advanced, gorgeous, sophisticated, and intuitive uses of Modern UI imaginable. They need to fully embrace the Windows Store for the entirety of the Microsoft library, and train users to feel okay about storing a credit card on their Outlook Mail accounts, and comfortable purchasing expensive programs without visiting Best Buy or Walmart. If they can't force corporations to migrate their moribund Visual Basic 6 applications, they can wow companies and shame them with the incredible technology that they're missing out on. "Embrace Windows 8 and you'll see massive, long-term productivity increases by way of this magical new platform and interface." 

That is not what they are doing, and to see how Microsoft is failing to lead the way on Windows 8 development, all you need to do is install Office 2013. It's impossible to overstate the importance of Office to Microsoft's continued relevance in the changing marketplace. (Microsoft has all but acknowledged this by withholding the completed Office for iPad. Once it hits the App Store, there will be no compelling reason for businesses to invest in Surface tablets.) It's the one software suite every business in America is going to purchase en masse, and every consumer out there will want some part of, even if it's only a word processor.

Office 2013 is therefore the one program that Microsoft absolutely must have in the Windows Store. And of course, it doesn't. You can buy it online or at Office Depot or through Office 365 (itself an interesting development to be discussed another day). But on its flagship software distribution channel — the place through which it wants every developer in the industry to submit and sell programs — Microsoft's most important suite is nowhere to be found. 

Let us grant that Microsoft is still working through the thorny issues of bulk licensing for enterprise, and needs another year to get it right. Let's say billions of dollars are on the table if they get it wrong — billions that might end up at One Infinite Loop. At a minimum, then, Microsoft should show us the indisputable power of live tiles and the Modern UI, with databases processing information in real time and displaying results alongside slabs of sports scores and headlines. When Visual Studio is compiling a massive program, give us a live feed of the progress. More substantively, Word and Excel should leverage internally the power of Modern UI. (To see what a truly innovative embrace of the new aesthetic might look like, check out this jaw-dropping mockup of Steam for Windows 8.)

Here is what actually happens when you install Microsoft Office 2013: It creates the six most uninteresting legacy icons on the entire Modern UI interface. These icons do nothing but stare back at the user. Middle school students only a few months advanced beyond "Hello, world!" would take greater pride and infuse greater imagination in their Windows 8 tiles. Regardless, having failed at the aesthetic, maybe when you click the icons, Office demonstrates exactly what is so powerful about the new interface, and why Microsoft has bet the company on its adoption.

No. Clicking Word or its brethren pulls up the legacy desktop and runs the program from a traditional window. The program's look is updated from Office 2010, but is no more essential or unique to Windows 8 than Office's sorry excuse for live tiles. To be clear, the icons, however plain, work, and Office is as solid and unobtrusive as ever. But that wasn't the standard Microsoft needed to strive for. They needed to show the world why a world without Windows 8 would be a sad world indeed. In this, Microsoft failed to close the deal on the very fine Windows 8.