Randall said it's important to identify your strengths and weakness. Someone with a strong technical background may not have the right skill set for a management role. Equally, someone with strong interpersonal skills may struggle with a technical position.

Executives around the world say the events that have had the most profound effect on their careers originated largely at work, not from family considerations or changed personal aspirations, according to the latest McKinsey Quarterly survey.

The biggest challenge to changing careers is identifying your transferable skills and then learning how to package them to appeal to an employer in a different industry.

For 25 years, when people have asked me for career advice, what I always tell them is don't give up what you have inside. Never sell your soul – because no one can ever pay you back.