Ngozi Okonjo-Iweala

Nigeria, with the oil sector, had the reputation of being corrupt and not managing its own public finances well. So what did we try to do? We introduced a fiscal rule that de-linked our budget from the oil price.

And I think that still is true of this business - which is basically research and development - that you probably spend more time in planning and training and designing for things to go wrong, and how you cope with them, than you do for things to go right.