It appears that the upcoming Quantum Break game won't be available on Steam as it will be a Windows Store exclusive title.
While the big news was that Quantum Break will be after all ariving to the PC and won't be a Xbox One exclusive as well as feature DirectX 12 support, it appears that Microsoft has some other news about the upcoming title, as it will be exclusively available on Windows Store.
Microsoft might have some issues with such move as Rise of the Tomb Raider from Windows Store already had some issue regarding multi-GPU performance and issues with third-party overlay programs like FRAPS or MSI Afterburner.
Hopefully, Microsoft will be able to fix those problems and this is definitely a good way to promote its platform.