What I should have realised - and eventually did - was that the kind of person I was had no relevance. It wasn’t that I needed to change (the evidence suggests that we can’t do that anyway). All I had to do was change what I was doing. Success comes not from what your personality happens to be, but from choosing the course of action that best suits the position you’re in at any given moment.

Put like that, it seems obvious, doesn’t it? And yet we behave all the time as if personality is the key. Business firms give prospective candidates personality tests. When we interview new teachers, we try to weigh up what kind of people they are. Yet we only have to look around to see that success in the classroom, in leadership, in administration, in being a cleaner or a dinner supervisor has much more to do with what people do than what they are. Have you ever (be honest) appointed a newly qualified teacher, having been won over by personality, only to find that he or she didn’t actually do the job very well?

An excellent book I’ve been reading about this - Performance: The Secrets of Successful Behaviour by Robin Stuart-Kotze (Prentice Hall) - tells us there is hard evidence that only 10 per cent of the variance in a person’s behaviour is down to their personality. He is suspicious, for example, of the many definitions of “management styles”. ”‘People-oriented’ describes an attitude or value,” he writes. “But what behaviours need to be exhibited to demonstrate people-orientation?”

What’s needed for improvement, then, is for each individual first to know and understand the effects of what they’re already doing, and then to realise what they need to change. Secure improvement starts with individuals doing things differently - it’s bottom-up, not top-down.

Stuart-Kotze quotes management guru Peter Drucker: “The only true expert is the person who does the job.”