How much is a good reputation worth? Volkswagen recently demonstrated the cost of a bad one: in the two days after its emissions scandal broke, its share price plummeted, wiping out almost almost $28bn in market value. On Wednesday, the broader cost of that scandal became clear when the carmaker announced a loss of $3.86bn, its first quarterly loss in 15 years. But, while VW’s crisis was a striking demonstration of the high price of…