Like the best of us, the mega rich aren't immune to making epic mistakes. Even the shrewdest, most money-conscious billionaires such as Jeff Bezos and Warren Buffett have committed monumental blunders that have cost them dear. We take a look at 10 of the most expensive bungles of all time.

Richard Branson may be worth a cool $5.1 billion (£3.9bn), but the British tycoon has presided over plenty of failed ventures, including turkeys like Virgin Clothing, Virgin Cars and Virgin Brides. His biggest business blunder, though, has got to be the cola brand he launched in 1994.

Grossly underestimating the competition, Branson seriously thought he could take on Coca-Cola and Pepsi, and make a meaningful dent in the global soft drinks market. In reality, Virgin Cola bombed, despite massive ad campaigns and product placement in shows like Friends and Ally McBeal.

Branson's cola captured just 0.5% of the American market and had to cease US operations in 2001. The brand initially survived in the UK but was pulled from supermarket shelves in 2009 due to its waning popularity. Production halted in 2012 and the drink, a major flop, was consigned to history.

Read more on Branson's incredible investments that did work: From records to rockets: how Richard Branson made his billions

With her net worth hovering around the $1 billion (£765m) mark, top-selling author JK Rowling can certainly afford to splash out on the finer things in life. In late 2015 or early 2016, the Harry Potter writer snapped up her very own yacht, paying around $27 million (£20.7m) for the privilege.

Rowling had fallen in love with the classically styled schooner after chartering it for a holiday. Bolstering its allure, the elegant five-cabin boat once belonged to actor Johnny Depp, who named the vessel after the Greek sea goddess Amphitrite.

Rowling clearly had a drastic change of heart because just eight months after she bought it, the yacht was put up for sale at the vastly reduced price of $19.2 million (£14.7m) – $7.8 million (£6m) less than she paid. 

Perhaps Rowling should've bought one of these: Billionaire boats to blow your mind and your wallet

The richest person on the planet, Jeff Bezos is sitting on a $157.3 billion (£120.3bn) fortune, and few can dispute the Amazon boss has the Midas touch. Yet, Bezos has made some dire business mistakes in his time...

Top of the list is the ill-fated Fire Phone. In an attempt to compete with the likes of Apple and Samsung, Amazon launched the device in 2014 to much hype, but the phone's excessive price-tag, awkward OS and limited ecosystem spelled its downfall.

The phone failed to sell, even when it was reduced in price from several hundred dollars to just 99¢ (76p). Needless to say, Amazon quietly discontinued the device the following year and had to write off $170 million (£130m) in the process.

Rocking a net worth of $17.2 billion (£13.1bn), financier and corporate raider Carl Icahn is a legend on Wall Street, but even the most renowned investors in the world can make grave errors of judgement, and Icahn is no exception.

In 2004, Icahn poured $191 million (£164m) into the Blockbuster video rental chain, which boasted a market cap of $5 billion (£3.8bn), thousands of stores in the US and a workforce of 84,300. But the company was in deep trouble.

Intense competition from Netflix, video on demand and automated kiosks during the mid to late 2000s pretty much killed the business, which failed to adapt. Icahn eventually called it a day in March 2010, selling his portfolio of shares at an enormous 98% loss.

Oprah Winfrey has overcome all sorts of obstacles to get to where she is today, and like the other billionaires in this round-up she hasn't let the mistakes she has made along the way hold her back. But the Queen of All Media suffered a major setback in 2011 when she launched her own network.

Winfrey made the mistake of rushing the launch of OWN, and admits in hindsight that she was woefully unprepared. Within a year, ratings had slumped and several flagship shows, including a pricey Rosie O'Donnell talk show, were axed.

The ratings tumble is estimated to have cost the network $330 million (£252m). Fortunately, Winfrey has since managed to turn it all around, partly thanks to Tyler Perry, and her net worth is topping an impressive $2.8 billion (£2.1bn) at the current time.

Read about Oprah Winfrey's incredible rags-to-riches story

Newscorp head honcho Rupert Murdoch, who is no doubt reeling right now after losing control of Sky, came a cropper in 2005 when his company parted with a hefty $580 million (£444m) to acquire MySpace, which as you may fondly recall, was the hottest social media site at the time.

Newscorp was looking to cash in on internet advertising and use MySpace to drive traffic to its newspaper sites. A foothold into the wonderful world of the internet, MySpace seemed like a sure-fire bet. Then Facebook happened.

The competing social media site exploded in popularity and MySpace began losing users in their droves. MySpace was eventually offloaded by Newscorp in 2011 for just $35 million (£27m). But don't feel sorry for Mr Murdoch. The media baron has a real-time net worth of $18.6 billion (£14.2bn), so he won't be going broke any time soon.

Confident that he could conquer the fast-growing US PC hardware market, Mexican retail and telecoms tycoon Carlos Slim acquired underperforming computer chain CompUSA in 2000 for around $800 million (£612m).

Slim, who has apparently never used a computer, went on to pump millions of dollars into the failing chain. But try as he might, the magnate, who was the richest person in the world for a number of years, just couldn't make it work.

The rise of the laptop – CompUSA specialised in desktop PCs – and the shift from physical to online stores were the death knells for the chain, which was sold off to a private equity firm for peanuts in 2007. Slim, who is currently worth $63.1 billion (£48.5bn), lost around $2 billion (£1.5bn) all in all.

Hungarian-American investor George Soros has pulled off some spectacular financial coups in his time, including his audacious short sell of sterling in September 1992, a move that netted his Quantum Fund $1 billion (£765m) and made him the 'man who broke the Bank of England'.

Soros may have lucked out with sterling, but his gamble on the Russian ruble in the late 1990s was anything but fortuitous. Quantum Fund had invested heavily in Russia, mainly in equities and bonds.

The country's economy came crashing down in 1998, and the Russian government ended up devaluing the ruble and defaulting on its debt. As a result, Soros lost a total of $2 billion (£1.5bn). Today, Soros is worth $8.3 billion (£6.3bn), having given away billions to good causes.

Elon Musk's Twitter rants have hit the headlines for all the wrong reasons this year, and have made investors very nervous indeed as the behaviour of the controversial billionaire has become ever more erratic.

Musk's misjudged tweet on 7 August announcing that he was considering taking Tesla private has been the most financially damaging by far. The firm's share price surged initially, but when it transpired funding hadn't actually been secured, the price tanked.

In fact, Tesla has lost over $10 billion (£7.7bn) in market cap since August, impacting on its CEO's net worth, which stands at $20.8 billion (£15.9bn). Adding to the tech tycoon's problems, Musk is now under investigation by the US Department of Justice over the tweet, which may have broken federal law.

Read more on the billionaire maverick: Elon Musk's incredible success story

Warren Buffett is one of the world's most successful investors hands-down. The 'Oracle of Omaha' is currently worth $89.3 billion (£68.6bn) and it seems like everything he touches turns to gold. But even Warren Buffett gets it wrong on occasion.

The Omaha-based investor has admitted his biggest mistake was acquiring Berkshire Hathaway in 1964. Buffett purchased the failing textile company partly to get back at the CEO, who had upped the price of the firm's stock, reneging on a deal the pair had struck.

Incredibly, Buffett believes that if he'd bought an up-and-coming insurance business instead, his holding company would be worth twice as much as it is now, a figure than runs into the hundreds of billions of dollars.

Not put off by their past mistakes, read about: Billionaires' extraordinary pet projects to transform the world