Narendra Modi's defining qualities are a sense of purpose.

If there is one lesson we have learned about leadership in recent years, it is that we overvalue intelligence and undervalue determination. When choosing our leaders we betray an instinctive bias for thought over action even though history teaches us that great leaders were great doers, not great thinkers. Outstanding leaders have always had the qualities of resolve, purpose and determination in abundance, and this helped them to change the world. With a PhD from Oxford University, our last prime minister was probably the leader most generously endowed with intelligence and academic credentials. But he failed. He neither had the willpower to prevail over events, nor the ability to translate thought into action. Sickened by the drift and paralysis of the last government, the Indian voter has now chosen the opposite type of leader.

Narendra Modi's defining qualities are a sense of purpose, accompanied by attention to detail, and backed by plenty of grit and fierce determination. These are quintessential abilities of an implementer, someone who knows how to get things done. These qualities were on generous display during his election campaign and if he runs the country as well as his campaign we have good reasons to be hopeful. The answers to India's problems have less to do with new ideas and new laws and more to do with implementing old ideas and old laws. Modi reminded us of this truth time and again during the past year, and those who know him well have said the same thing-his strength lies in execution. It is time we had an executive in charge of our country, someone capable of delivering results. It is for this reason that I-a liberal, secular Indian who does not find Hindutva or BJP particularly appealing-voted for him.

Indians do well in strategy, lag in execution

McKinsey & Co, the respected management consulting company, discovered in a famous global study in the 1990s that high performing companies distinguished themselves by execution. Its data on India reinforced the bias for action. In its sample of 35 major Indian companies, based on interviews with more than 600 executives, it concluded: "While many Indian companies perform well on strategy, they are lagging in execution.

Foreigners sometimes remind us that Indians are bright. But they are too polite to add that they can also be 'over-smart'. Indians think and argue too much, see too many angles, and don't act enough. It makes hiring and recruiting talent particularly difficult, for we come out sounding good in interviews, and how do you separate the doers from the talkers? The gap between thought and action is so pervasive in Indian life that I sometimes despair if weak execution is, in fact, a deficit in character.

My experience as a practising manager and later as a board member or consultant confirms that while most managers usually achieve a reasonably robust strategy, they implement poorly. I am also associated with a private equity fund that has invested in many Indian companies over the past 10 years, and it has reinforced this conclusion: The best firms are not the ones with the best business model but the best execution ability.

The story of Narendra Modi's climb from serving chai to passengers on the railway platform of a sleepy Gujarat town to 7, Race Course Road illustrates many things, including his leadership style. As he rose in life to take on positions of increasing responsibility in the RSS and later in the Gujarat government, Modi was not content with laying broad policies. Unlike our previous prime minister, he did not abdicate responsibility for implementation to those below him. He surrounded himself with people with execution ability like himself, set clear, measurable goals, and created small 'implementation' teams. Instead of pronouncing on strategy, he got into the messy details of a project, monitored day-to-day performance, removing obstacles for those who were implementing it, staying close to them and motivating them. He recognised those who took initiative and risks, and punished those who played safe and behaved like bureaucrats. And he did all this without appearing to be interfering or micro-managing. Thus, he got fairly ordinary Gujaratis to do pretty extraordinary things.

I first heard Narendra Modi speak at Shri Ram College of Commerce in Delhi in February 2013, and it opened a window to his leadership abilities. It was his first speech in a long campaign to be prime minister, and he declared his ambition right away. Unlike coy Rahul Gandhi and the Congress party, who danced coquettishly around the subject, Modi sent an unambiguous message that he was hungry for the job. He was off to a head start, and his clarity of purpose was refreshing for the Indian voter.

Modi was also unambiguous about his specific goal-it was to gain a clear majority for the BJP. The chattering classes laughed each time he said it and thought he was mad. They did not know that impossible ambitions drive successful leaders. Managers call these 'stretch' targets, and their purpose is to rally troops around difficult tasks. Impossible targets have a way of motivating soldiers who forget their differences. They feel they 'own' the goal and the battle. Thus, charismatic leaders are known to achieve astonishing commonness of purpose among their subordinates-what business managers prosaically refer to as 'alignment'.

Great leaders are not nice people

Related to this, was another feature I observed about Modi's campaign-the importance of a unified team. Great leaders are not 'nice' people who seek popularity, and certainly not ones you would invite to a polite dinner party. Narendra Modi had to ensure unified command and had to get rid of rivals and sceptics, which explains why he had to marginalise L.K. Advani, Jaswant Singh and others. And why, at the same time, he had to move his most trusted lieutenant, the ambiguous Amit Shah, to perform the miracle of turning Uttar Pradesh around. And why, despite opposition from inside the party, he tied up with unsavoury, blemished politicians B.S. Yeddyurappa and Ram Vilas Paswan.

The word executive comes from 'one who executes'. The hallmark of an effective executive is good planning and attention to detail, which is an important lesson I learned at the company where I worked for many years, Procter & Gamble. (The other lesson was how to write a crisp one-page memo because you were not allowed a second page). Modi, as I have said, is an implementer, and hence planning and detail come naturally to him. What we saw on television was great oratory but behind the scenes was months of planning with dozens of karyakartas, who worked with discipline to orchestrate each event minute by minute.

Finally, Modi is a flawed individual, not unlike most of us. In his place, I would have expressed remorse a dozen times for the events in 2002, without of course, incriminating myself. I would have had a powerful think tank to feed me data, especially on economic and foreign policy issues. I could go on and on about his deficits. But at the end, his positive attributes clearly outweigh his faults. If there is one truth I would underline it is that without realising it, Narendra Modi seems to follow the British scientist Jacob Bronowski's advice. He believes that the world is not understood by contemplation but by action-"the hand is the cutting edge of the mind, as Bronowski put it.