What is the best way to select talented staff? The established process is to identify a set of desirable qualities and then select candidates who are at least average across all of these qualities. However in this line of thinking, the pebble - a candidate who is entirely average, is more valuable than a flawed diamond – a candidate with an exceptional skill, who is below average in another respect.

So, why does this happen and why is it wrong? One of the key reasons this happens is because humans have evolved to be risk averse. Our motivation to avoid a loss outweighs our appetite for a potential gain. For example, research shows that most people are unwilling to accept a 50-50 bet unless the amount they could win is roughly twice the amount they might lose . This reluctance is known as loss aversion and it influences decision making in a wide variety of domains. In recruitment, loss aversion leads us to a low-risk approach, where a ‘safe-pair of hands’ is favoured – the pebble without imperfections.

Our instincts betray us, however. This approach is wrong because highly successful people have what is referred to as "spiky competency profiles". In simple terms this means that they have very clearly defined strengths but they also have weaknesses. Sir Isaac Newton was one of the most influential thinkers the world has ever seen. He has been described as ‘a supreme genius’ and ‘brilliant beyond measure’. However, he was also ‘solitary, joyless, and prickly to the point of paranoia’ . It seems fair to say that he would struggle to pass a modern assessment centre.

Sir Richard Branson is also highly successful, albeit for very different reasons. By his own admission, he is not academically gifted and was often bottom of the class at school, due to his dyslexia . However, his entrepreneurial nature and appetite for risk have contributed to the success of his Virgin group of businesses, with revenues in 2006 exceeding £10 billion. Importantly, it is clear that Isaac Newton and Richard Branson were successful because of their exceptional strengths, not because of any lack of weaknesses.

A second reason why traditional selection processes are wrong to reject candidates with "spiky profiles" is that success does not require all people to do all things. Successful teams have complementary strengths – the creative instigator, the well-organised co-ordinator and the driven completer-finisher. It is implicitly understood that all of these roles have "spiky profiles" - there are distinctive strengths and areas of weakness. In combination, however, they lead to success.

What then is the way forward? There are three key steps. First, look for excellence – genuine excellence – in one area. This is the distinctive strength that will be the cornerstone of that person’s future success. Second, look for a high level of self-awareness. This provides the insight to maximise a distinctive strength and to mitigate weaknesses. Without self-awareness highly successful people can derail because they fail to compensate for weaknesses or because they misuse their strengths . Finally, actively seek-out a diverse range of candidate strengths. This will ensure that your organisation has excellent performers for every important activity. In summary, next time you are recruiting, remember that a flawed diamond is worth more than a pebble without imperfections.