As the saying goes, if you stay in the middle of the road for long enough, chances are you'll get run over. Today, the 'Big Four' are matched (or beaten) on quality and price by competitors and new arrivals. It's increasingly apparent that nobody really loves them, nor can they think of a reason to keep shopping with them anymore.
It was always Gordon Brown's problem. It's turned out to be Philip Clarke's as well over at Tesco. And, despite his recent runs for England, it may well be Alastair Cook's too. But why are deputies so often such failures? Why, when they have spent years planning their accession and have been positively groomed to take over, do they invariably make such a hash of the top job?