Charles Dunstone is nothing if not determined.

The 41-year-old may have admitted to being plagued by waves of self-doubt personally but there are no signs of it in his aggressive market moves.

Instead, Mr Dunstone’s company has achieved, as he described it in a recent interview, a “level of influence beyond my wildest imagination”.

The sense of the challenge is something that the non-university educated Mr Dunstone seems to relish.

He founded The Carphone Warehouse in 1989 when mobile phones were still a niche market and is among the founder members of Business for New Europe, a forum set up to encourage economic reform in Europe.

One of his main hobbies is the highly competitive sport of yachting and he is a former Cowes Week winner. He still plans to find the time to compete this year as well as racing for the Britannia Cup and the New York Yacht Club Challenge Trophy.

He might be prepared to give credit to others for ideas, praising a UK business manager for the group’s big Christmas success story – an exclusive shocking pink Motorola V3i – but, in return, he requires dogged commitment.

Business lunches at The Carphone Warehouse, for example, are discouraged. “We just try harder. If you aim just to do the same as everyone else, you won’t succeed.”

His “try harder” mantra has turned £6,000 of savings – invested into the business with schoolfriend David Ross – into an estimated personal fortune of more than £900m.