"We have the Windows Phone OS. We have Windows RT and we have full Windows. We're not going to have three."
For Microsoft's head of devices, Julie Larson-Green, believes Redmond could operate in a world where just a single version of Windows exists.
Speaking at the UBS Global Technology conference last week, Larson-Green offered the strongest indication yet that the software giant has too many operating systems.
"We do think there's a world where there is a more mobile operating system that doesn't have the risks to battery life, or the risks to security," Larson-Green told the audience.
"But, it also comes at the cost of flexibility.
"So we believe in that vision and that direction and we're continuing down that path."
Larson-Green's comments echo those of Terry Myerson, the Windows chief who in September this year claimed the company is organising its OS groups around three key values: commonality, the cloud and tailored experiences for devices.
"The first of those is that we really should have one silicon interface for all of our devices," Myerson said at the time.
"We should have one set of developer APIs on all of our devices. And all of the apps we bring to end users should be available on all of our devices."
"The second belief was that all of our devices are becoming more cloud-powered.
"So whether we're branding them Windows or Xbox, we really need one core service enabling all of our devices.
"The third belief is that while Microsoft is using a common Live Tiles interface across Windows, Xbox, and Windows Phone, the experience needs to be tailored per device.
"We want to facilitate the creation of a common, a familiar experience across all of those devices, but a fundamentally tailored and unique experience for each device."