Free upgrades would also set a precedent, Dawson observed, that might be difficult to later reverse. That alone makes Microsoft's Windows 10 decision important: It could be stuck with what it chooses in 2015. In some ways, however, that hesitation to break with precedent would be minimized. Most analysts expect that Windows 10 will be the last major upgrade, if not for forever, then for many more years than the usual three-year cycle, with constant updates replacing occasional upgrades.
Perhaps Microsoft believes the benefit of a widespread free upgrade -- anything more than Option A -- outweighs the revenue and OEM relationship problems. If so, one reason has to be its app issue.
Before the launch of Windows 8, then-CEO Steve Ballmer boasted that Modern app developers would have hundreds of millions of customers, basing that on the number of PCs sold annually, plus anticipated upgraders. "It's going to create a heck of a lot of opportunity for folks in this room to make millions," Ballmer claimed in October 2012.
That opportunity did not materialize. But a free Windows 7-to-Windows 10 upgrade has the potential to add millions more to the pool of app purchasers, and millions of buyers of what Turner called "services and different add-ons."
Microsoft may not strike out with just one whiff at the app plate, but it's hard to see how it could convince developers that Modern is worth their time if it swung and missed again with Windows 10. This might be its last chance.
"In some ways, Windows 10 may be seen as symbolic of all the challenges facing Microsoft," said Dawson.
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