Success and how it is measured continues to be one of the "known unknowns" for MOOCs. Debate (hype) on success is heightened by the now recognised and recorded high drop out rates. If "only" 3,000 registered users complete a MOOC then it must be failing, mustn't it? If you don't get the certificate/badge/whatever then you have failed. Well in one sense that might be true - if you take completion to equate with success. For a movement that is supposed to be revolutionising the (HE) system, the initial metrics some of the big xMOOCs are measuring and being measured by are pretty traditional. Some of the best known success of recent years have been college "drop outs', so why not embrace that difference and the flexibility that MOOCs offer learners?
Well possibly because doing really new things and introducing new educational metrics is hard and even harder to sell to venture capitalists, who don't really understand what is "broken" with education. Even for those who supposedly do understand education e.g. governments find any change to educational metrics (and in particular assessments) really hard to implement. In the UK we have recent examples of this with Michael Gove's proposed changes to GSCEs and in Scotland the introduction of the Curriculum for Excellence has been a pretty fraught affair over the last five years.