If companies adopted OpenGL over DirectX out of the gate, they could build games for all 3 platforms in one shot with a little conditional compilation with encapsulation. E.g. They build a FileSystem/Sound layer for Linux, Windows, and Mac from day one, then use conditional compilation to build the game for all 3 plats. It wouldn't cost them much more if they did it from day 1. And OpenGL is arguably as good or better than DirectX. Microsoft is even considering supporting WebGL in IE 11 and has rumored a tablet with Windows and Android installed. They could be changing their ways in the future.