NOBODY LIKES banks. Their technology is often primitive. Their users are hit with unpredictable fees. Their functions matter, yet their coverage is incomplete. This can relegate swathes of people in rich countries and entire populations of poor ones to the fringes of society. Many of the biggest make most profits from trading and fees, not providing services to ordinary customers. And worst of all, their failures can cause catastrophic damage for which they bear only a fraction of the costs.