The authors behind the report said it was "clear" that chief executive candidates need more preparation in terms of how to cultivate and manage culture change.
"This study shows, we believe, that as confident as many chief executives are, there are many aspects of the role that they are not prepared for – and possibly cannot prepare for in the traditional sense," says Egon Zehnder's Kati Najipoor-Schuette.
Partha Goswami, chief executive of online marketplace OOSTOR.com, which launched last year, said the role of chief executive is often seen as glamorous, but in reality you spend "hours pulling out your hair trying to solve every problem under the sun".
"As chief executive it isn't just yourself you need to worry about," he says. "You need to be a mediator between departments and staff, you have to ensure people get on and work productively with each other. It takes a lot of energy to maintain an effective workplace chemistry."
Goswami says that having shareholders added an extra layer of pressure, "as all responsibility and blame falls on the chief executive".
She adds: "If you have shareholders it is even more pressure, they will be asking constant questions regarding returns and business progress, and as CEO you are the one held accountable."
Mark Cuddigan has been at the helm of the £65 million ($125m) baby food brand Ella's Kitchen since 2013. Because the company "values autonomy and responsibility for everyone in the business", Cuddigan says he felt prepared to step up from his role as sales and marketing director because he was already used to the pressure of decision-making.
Dealing with the purchase of Ella's by a NASDAQ-listed American company was one aspect of his role as chief executive that "brought many surprises", he says.
"But I can honestly say that the daily reporting aside, it's been an inspiring journey."
Much of the pressure of being chief executive is self-imposed, Cuddigan says. "I put a great deal of pressure on myself, as I know what an extraordinary company Ella's is, and how much the brand means to so many parents and little ones. I try very hard to make Ella's the best possible place to work."
Steve Magnall, chief executive of Suffolk-based independent brewery St Peter's, agrees that the greatest pressure comes from himself, "because I know that if I get it wrong, the livelihoods of the 47 people I employ are at stake".
Magnall joined the brewery as chief executive two years ago to implement a turnaround strategy, focusing on reducing costs, increasing productivity and boosting retail and trade opportunities.
"The biggest shock when I became chief executive was dealing with the tight cash flow and making people understand that it isn't about turnover, but about how much cash is coming through the door and how much of that you keep.
"It takes 90 days for supermarkets to pay us for our bottled beers, so our outgoings are more frequent than our incomings.
"I didn't expect to be having arguments with bank managers as the chief executive."
As well as getting to grips with the implications of a tight cash flow, Magnall says that one of the biggest difficulties he faces as the boss was getting his team to understand how market dynamics work.
"Most of the people in the company were born and raised in Suffolk, so their understanding of the wider world of leisure and the drinks industry was somewhat limited. I made it a priority to introduce training and development initiatives and now the team fully understand the industry."
Frank Jan Risseeuw says that the reality of becoming the boss of money management app Yolt was not too dissimilar from his expectations.
"I've found that being chief executive is a real juggling act between your own work and supporting the wider team, ensuring they remain focused, motivated and have everything they need to do their job to the best of their ability.
"The title of chief executive does not determine who you are. Like any position the role is what you make of it, the responsibilities you choose to take on, and how you conduct yourself."