Every incoming chief executive wants to see their employer’s share price pop on the news of their appointment. No outgoing boss wants to witness the same thing happen when they announce their departure—especially if a market-wowing successor has yet to be named. That was the fate that befell Alan Jope after he declared on September 26th that he would retire next year. The market value of the consumer-goods giant popped by as much as 3.5%,…