Another stumble with the next Windows won't stop OEMs from shipping Windows on their machines -- as Moorhead noted, the alternatives are meager -- but it would open the OS to even more inroads by rivals.
"Windows 8 has given iOS, Android, Chrome OS and OS X more and greater access to the enterprise," said Moorhead. "Microsoft has a chance to turn around the perspective [of Windows] with Threshold and minimize the risk [of further erosion]."
Threshold is important because, as Moorhead and others have pointed out, enterprises should already be looking ahead to what they will use to replace Windows 7, which has become, like Windows XP before it, the OS standard bearer for business.
While Microsoft will provide security updates for Windows 7 until January 2020, companies that want a smooth migration from old to new should be planning now for its replacement, Gartner analysts said last month. That replacement could be Threshold, if Microsoft effectively makes its case starting Tuesday. "[Microsoft] needs to give customers an idea of what the road map is going to be," said Gartner analyst Michael Silver in an August interview.
If Threshold is simply a warmed-over Windows 8, then enterprises may well postpone migration plans and hope that whatever comes after that is more palatable. But during the interim, there's the chance that they will look even harder at alternatives, like Macs and Chromebooks. Although neither can conceivably supplant Windows, PC sales are a zero sum game at this point: Every machine sold with Chrome OS or OS X is a loss, perhaps permanently, to Windows. And thus the spiral quickens.
"Threshold will either put points in Windows' column, or in [those alternatives'] columns," said Moorhead.
At least Microsoft has history on its side: Since Windows 98, the company has alternated well-received and rejected editions.
"Ideally, this next version of Windows will continue an amazing streak of alternating releases," said Rubin. "There was Windows 98, which was good, and then Windows ME, which wasn't. There was Windows XP, then Vista. Windows 7, then Windows 8. So this is an opportunity to address their users' demands, as they have historically done."
"I'm hoping for the best," said Miller. "I like what I'm hearing [about the next Windows]. But this is make or break."
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