The study found that business owners with above average optimism, like those who appear on Dragons’ Den, earned 30 per cent less than those with below average optimismCredit:BBC/PA Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. “If you are an optimist, then watching those shows may well encourage people to enter self-employment.“As a society we celebrate optimism and entrepreneurial thinking – but when the two combine, it pays to take a reality check.“Every episode of the BBC’s Dragons’ Den provides examples of such wishful thinking. Pessimism may not generally be seen as a desirable trait but it does protect people from taking on poor entrepreneurial projects.”Tracking individuals as they move from paid employment to setting up their own business venture, the study found that business owners with above average optimism earned 30 per cent less than those with below average optimism.The new findings could help explain why only 50 per cent of businesses in the UK survive their first five years.In 2016, 414,000 businesses were set up in the UK, against 328,000 business failures in the same year, according to figures from the Office of National Statistics. Show more Dr Dawson added: “You watch [Dragons’ Den] and, if you are more of a realist, you wonder why on earth did these people think this idea would catch on? Why have they invested all their money in it? It’s not going to work.“This is quite common in entrepreneurship, so you get people setting up these crazy businesses that are never going to make any money.“Even people who do get money in Dragons’ Den, they are successful in securing venture capital. But then only 5 per cent of those businesses end up making any money.”The study also criticised the Government’s “far too encouraging” approach to entrepreneurship.LSE Professor David de Meza said: “Governments frequently talk about the role of entrepreneurs in creating economic growth, but there is a downside.“The personal and societal fall-out of failed businesses shouldn’t be underestimated, which is exactly what optimists do. Policy makers should not encourage the wrong sort of start-up.” Dr Dawson added: “The Government should focus on the right kind of start ups. It’s far too easy to get small start-up business loans now.“People don’t need encouragement. There are enough people who think that they can make it as entrepreneurs. What the Government really need to focus on is creating much fewer startups but higher quality and higher chances of success, which ultimately create jobs and wealth.”The BBC was approached for comment. Dragons’ Den is encouraging too many “wishful thinkers” to set up businesses doomed to fail, university researchers have suggested. The popular BBC TV show, where hopeful entrepreneurs try to secure financial backing from five successful millionaires, is full of “people overestimating their ideas and their ability to make money”.A study by researchers at Bath University, London School of Economics and Cardiff University, found that optimism – like that frequently seen on Dragons’ Den – is leading people to set up businesses that have no realistic prospect of financial success.Dr Chris Dawson, Associate Professor in Business Economics at the University of Bath, said “the biggest chunk” of Britain’s business failures is down to overly optimistic people thinking they can start them in the first place.–– ADVERTISEMENT ––Speaking to the Daily Telegraph, he said: “When I watch Dragons’ Den, I think that’s exactly what my research is all about – people just overestimating their ideas and their ability to make money.