Andrew Silvernail grew up in a small town in the US state of Maine, where the local paper mill was one of the few businesses in the area.

Becoming the CEO of a global business never entered his mind; he had planned to be a doctor. “I didn’t even know what a business was,” he says. “I’m not being facetious.”

Silvernail caught the business bug in university, after helping a local businessman, a CEO of family run construction company, launch a political campaign. “He was an incredible value-driven person,” he says. “He had a sense of mission and tried to improve people’s lives.”

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Later, while working as an analyst at financial firm, he met the chief executive of another company who suggested he should one day run a business himself. At the time he brushed off the idea – many of the famous CEOs he was aware of had an autocratic style of leadership that he didn’t like.

Over time however, Silvernail realised that people’s perceptions of what makes a successful CEO are sometimes wrong. He is now CEO of IDEX Corporation, a company worth $8.6 billion that develops numerous fluid-related products for the agriculture, fire safety and health industries.  It doesn’t matter if you’re introverted or extroverted, or have an overabundance of charisma, he says. What matters is how you treat employees, your work’s purpose, and being humble.

People who come from ordinary beginnings can reach the top - Elena Lytkina Botelho

“There are lot of powerful myths around what makes a good CEO,” says Silvernail. “Some [perceptions] are still strong, but some are starting to die.”

He isn’t the only successful executive who once questioned whether he had good leadership credentials. According to research conducted by ghSMART, a Chicago-based management consulting firm, there are many misconceptions around what makes a good leader – many of them debunked by the company’s research – and that’s caused many a potential executive to think twice about chasing the corner office.

“You might think no one would bet on you becoming a CEO in 10 or 20 years,” says Elena Lytkina Botelho, a partner at ghSMART and founder of The CEO Genome Project, a 10-year study that has examined thousands of CEOs to determine what makes a successful leader. “What we found is encouraging in that people who come from ordinary beginnings can reach the top.”

Myth 1: CEOs must be charismatic

One of the most pervasive perceptions of a good company leader is that they need to be overflowing with charisma. Think General Electric former CEO Jack Welch or Apple’s Steve Jobs, larger-than-life personalities who could command a devout following. It’s something many headhunters or boards often look for in a CEO. “I’ve had conversations with board members who liked a potential CEO, but were concerned about them being an introvert,” says Botelho.

But it turns out charisma is overrated. When Lytkina Botelho looked at what kinds of CEO exceeded their boards’ expectations, introverts did slightly better than extroverts. While many companies hire the outwardly confident candidate, in part because they give a good interview, they might be missing a trick. “Being more likeable and confident makes you more likely to be hired in that role, but it has no relationship to performance,” says Botelho.

Myth 2: CEOs shouldn’t admit when they’re wrong

Many CEOs have trouble owning up to a terrible mistake. Some see failure as a sign of weakness; others worry about how shareholders or board members might react.

Weaker candidates tend to blame others

Failure, though, is key to success. Botelho found that nearly all CEOs had made significant mistakes, with 45% of them messing up so badly that it cost them their job or it was a major detriment to the business. Among candidates that either derailed their career or nearly ruined their business, 78% ended up landing a top job.

The ones who could own up to their mistakes, and learn from them, were also the ones who had the strongest performance. “These are the people who can say ‘this didn’t go well, it was a disaster, but in hindsight I can tell you why,’” she says. “Weaker candidates tend to blame others or explain things away and that makes it harder for them to learn.”

Myth 3: CEOs need to be experienced in a particular sector

Just because someone hasn’t worked in a certain industry shouldn’t preclude them from a top job, says Alison Ryan, client services director at Executive Headhunters in Southampton. “Boards often believe that a CEO needs to have had experience their particular sector, when we can find that it can be a positive thing if they come from a different industry,” she says.

In many cases, people form outside of a sector can bring a fresh perspective, new skills or different ideas to a company. “They can apply them without any pre-conceived ideas that might exist,” she says.

Industry expertise can be learned, she says. Having a range of experiences and strong soft skills, like managing staff well, and having solid problem solving skills, can go a longer way than knowing the intimate details of a sector.   

Myth 4: CEOs must be autocratic

Many people think that CEOs need to be ruthless, which is an idea that GE’s Welch popularised. Every year he would segment his workforce into three buckets: the top 20% of workers would get showered with praise, the middle 70% would receive coaching and the bottom 10% would get unceremoniously fired.

As Silvernail got to know more CEOs though his work as a financial analyst and as a budding executive, he came to realise that autocratic management was a detriment to business success. “Most people aren’t as capable as Jack Welch, so when people grab onto certain elements of his character, or when behaviours are done in a vacuum, they are massively damaging,” he says. “There’s an idea that intimidation is leadership.”

 The most successful ones try to get buy-in from employees, boards and shareholders

While successful CEOs are decisive – ghSMART found that people who were thought of as decisive were 12 times more likely to be high performing executives – and make decisions with conviction, they often aren’t making those decisions from on high. The most successful ones try to get buy-in from employees, boards and shareholders.

While they can’t be too soft or too hard – you can’t please everyone, nor can you be a dictator – there is happy medium that yields the best results. “Think of the CEO as an orchestra conductor,” says Botelho. “You have to have the ability to engage stakeholders toward the benefit of the overall company without being too extreme one way or the other.”

Myth 5: CEOs should have a top-tier education

Another myth is that you need to graduate from Harvard or Oxford to become a successful CEO. In fact, only 7% of the high-performing CEOs that The Genome Project studies had an Ivy League undergraduate education, while 8% didn’t even graduate from university.

Only 7% of the high-performing CEOs in the studies had an Ivy League undergraduate education

Jill Wight, a principal at private equity company The Carlyle Group, has hired many CEOs for the companies her firm invests in and agrees that a degree from a top school doesn’t by itself determine performance. “Strong intellectual horsepower” is a pre-requisite for success, she says, not the school you came from. “The presence of a degree is positive, but the absence of one isn’t by itself a negative,” she says.

A degree from a top school is even less of an issue in the UK, says Ryan, where social class, not intelligence, would typically determine who went to the best universities. People know that where you graduate from doesn’t reflect how smart or savvy you may be.

“It’s never a given in the UK that just because you have a certain level of intelligence that you would follow a particular route into higher education,” she says. “There a lot of other factors that determine where people go.”

For Silvernail, who is a high-performing CEO according to Botelho, being a successful executive comes down to three things: making life better for his stakeholders – that’s shareholders, employees and the community at large – truly understanding the business he’s in and being people-centric.

 “I want to be able to be great,” he says. “That’s my job – to create an environment where people can be their best every day.”

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