When the going gets tough, Christine Lagarde has often been called upon to broker a deal or find the solution to a conundrum that baffles lesser minds. In a word: she gets going and likens that to being suspended from a ‘glass cliff’ – as opposed to bumping against a glass ceiling – a phenomenon whereby a complex and hazardous job is handed to a woman, making her success improbable, and affording men a measure of plausible deniability.