The experience of Hakan Samuelsson, chief executive of German industrial group MAN, shows how some of the most effective bosses can be undermined when a single tactical move does not pay off. The Swede - the only non German-native speaker running a Dax-30 company - received a bloody nose last year after the failure of his hostile bid for Swedish truckmaker Scania, followed by Volkswagen's swoop to become MAN's biggest shareholder.

That rather overshadowed his massive restructuring of MAN, which he has transformed from a sleepy conglomerate into a highly profitable maker of trucks, diesel engines and turbines. The company has benefited greatly from growth in emerging markets such as eastern Europe, but Mr Samuelsson is now attempting to move beyond Europe's borders to turn the truckmaker into a global force to rival Daimler and Volvo.