They have dominated the rainforests of South America, the mountains of Peru and the kibbutzes of Israel for decades — and all in the name of broadening their horizons.

However, gap-year students are wasting their time, according to the head of world’s largest advertising and media company. Sir Martin Sorrell, chief executive of WPP, which has 190,000 employees in 112 countries, said he took a year out, but decided to work in a TV and radio shop and said he “didn’t believe” that gap-year travel benefited anyone’s career prospects.

Calling for a revolution in the way young people learn, he also said that computer coding should be compulsory in schools as the main foreign language, followed closely by Mandarin.

He told the Global Education and Skills Forum in Dubai: “Gap years tend to be ill organised and ill directed and more a serendipity. Companies don’t find them enough time [to do something useful].”

Sir Martin, 71, said he worked at the equivalent of Dixons, vetting hire purchase agreements, then in a shop in Harlesden, northwest London, selling radio and TV sets, during his gap year, adding: “I’m sure it fashioned and changed me, it was valuable.”

The son of Jewish immigrants, he went to a direct grant grammar school, the University of Cambridge and Harvard Business School, but said his education had been too narrow. “The best thing you can do is go and study in a foreign land. I don’t speak languages, my wife speaks five. I don’t speak code. Code should be compulsory in schools.”