Using real-time payments data and a risk-management system that analyzes more than 3,000 variables, Ma’s four-year-old MYbank has lent 2 trillion yuan ($290 billion) to nearly 16 million small companies. Borrowers apply with a few taps on a smartphone and receive cash almost instantly if they’re approved. The whole process takes three minutes and involves zero human bankers. The default rate so far: about 1%.