I first met Gerry Grimstone in the late 1980s, when he was a banker helping to oil the wheels of Margaret Thatcher’s privatisations. His career has since seen him win a knighthood and rise to chair Barclays bank and Standard Life Aberdeen. The Mail on Sunday called him “capitalism royalty”. Nobody has ever accused him of being insecure.

Yet at 69, he works from 7am to 11pm, six days a week, and cheerfully admits to an irrational fear he may not have done enough. “You never feel you have got there,” he says in a BBC radio documentary broadcast on September 24. “There’s always an element of dissatisfaction: if only I tried a little bit harder perhaps I could get to the next step.”

Another insecure overachiever, David Morley, former senior partner at law firm Allen & Overy, describes the excitement of participating in this vicious cycle as “l(fā)ike a drug”.