Bitcoin failure to expand and usable as a currency is the main reason many say Bitcoin is useless and they have true facts because in order for Bitcoin  to become the global currency in the world it should be used by majority of people not just for buying and selling but to use it has a means of payment for essential occasions  and it should be accessible to everyone though many sources and I mean not only from exchanges but from common places which might take several years to happen but it should happen in a higher rate and also for that to succeed Bitcoin price should become stable more than today