One of the most unusual challenges faced by life insurance entrepreneur Clive Cowdery when he was working for General Electric 20 years ago, was figuring out how to hide the people in his business he was supposed to sack.

Under the rules laid down by Jack Welch, the legendary chairman and chief executive of GE, the head of each business in the sprawling conglomerate was forced to get rid of the bottom 5 per cent of staff each year.