It has been revealed that the Xbox One is unable to play recordable Blu-ray discs.
HDTVTest has reported that they tried to play content from a recordable Blu-ray disc (BD-R). The site tried “single and dual layer discs of various brands” but the Xbox One wouldn’t play any of them.
If you recorded a family outing on a HD camera and recorded it on a Blu-ray disc for example, the Xbox One won’t be able to play it. It has been said the console can only play “mastered Blu-ray discs and DVDs”.
The reason the console cannot play recordable Blu-ray discs is to prevent piracy.