Learning from mistakes with a failure is not the same as a success.
Its quite clear to me that Xbox One was a catastrophic failure. The 360 has legendary status in terms of consoles. MS was setting themselves up for complete market domination, and back then market domination meant raw console sales figures - which leads to higher attach ratios and subscription services. For the most part, even up to today, success is still defined quite largely by the sales figures of the console. How was it not a failure.