There was a time when Jumia’s biggest competition was Nigeria’s army of informal retailers who operate in open markets and with flexible pricing. The new contest is with global platforms that can outspend, out-stock, and outsell local incumbents without ever opening a warehouse on the continent.The timing is especially difficult for Jumia. In earlier years, it was flush with capital and could burn cash to win market share. Today, it has a liquidity position of around $100 million on annual losse...