I just like to get to the start line knowing there was nothing else I could have done, that there wasn't a single session I didn't give 100 per cent. The physical certainty means you can relax mentally and let the performance come.

I always have, in my expeditions, people who are academically far cleverer than I am, and even technically, far more competent. So if you want to lead an expedition, in a sense, you’ve got to keep ahead of them. These bright, competent characters you have with you who are marvelous to have on the expedition. And I’ve always found you can do that by, each night, when you go to bed, just let your mind dwell on the likely things that may happen next day, and think out carefully the sort of decisions that might be necessary to make in order to have the program carried through. So next day, when something happens, you’re the one that’s thought about it and you’re the one who has the ideas.

Perhaps one character trait which does help is the ability to focus, and perhaps to be a little stubborn. If I learned something in class that I only partly understood, I wasn't satisfied until I was able to work the whole thing out; it would bother me that the explanation wasn't clicking together like it should. So I'd often spend a lot of time on very simple things until I could understand them backwards and forwards, which really helps when one then moves on to more advanced parts of the subject.

I was very, very thorough, making sure I really understood how that telescope worked, and that it was working properly. I was quite convinced that I wasn't clever enough to be in Cambridge and would be thrown out at some stage. My policy was to work as hard as I could so that I'd know I'd done my best. We now label this as impostor syndrome, but we didn't recognise, and certainly didn't name it, back then.

One cannot overemphasize the importance of observation and a full assessment — the failure to do so leads to some of the greatest mistakes, not only in war but also in business and government. A full assessment is critical. To properly manage any business situation, you need to perform a full and complete assessment of it. In business, you have to understand your competitors, their distribution, their economics, their innovations, and their strengths and weaknesses. You also need to understand customers and their changing preferences, along with your own costs, your people and their skills.