Microsoft's Satya Nadella says if OEMs don't make Windows phones they will

"If no OEM stands up to build Windows devices we'll build them. There will be Lumia devices. So I'm not afraid of saying, okay, it's all about the OEMs, or it's all about the ecosystem. It's about Windows. It is about the overall health of Windows and being grounded in any given day's reality, but having ambition of where the market is going versus being bound by current definitions."

http://www.windowscentral.com