My take on this is, I don't believe that Bitcoin failed on being a currency because there are still some people using it as currency regardless of its volatility. It may not be as successful as it is being utilized as an asset but that doesn't mean it failed on that area. I, myself, don't use it as a currency but there are still others who do, more and more establishments are accepting Bitcoin as payment already, i think that will continue still, at least from where I came from.