The old saying "if it ain't broke, don't fix it" often comes to mind when brands decide to change iconic formulas or familiar packaging. In fact, when companies decide to make a bold product change, it can backfire spectacularly.

From the Coco Pops re-brand that went horribly wrong to the Pizza Shapes recipe change that led 30,000 people to sign a petition in protest, read on to discover the product changes and rebrands that flopped.

All dollar amounts in US dollars.

Instead of capitalising on the 'Cool Britannia' movement of the 1990s, British Airways opted to replace its stylised Union Jack livery with artwork representing the many nations served by the airline. Regarded as one of the worst marketing blunders of all time, the 'World Images' tailfins were loathed by many passengers.

In 2001, just four years after the artwork was introduced, BA bowed to public pressure and reinstated its abstract Union Flag design. 

In 1998, Kellogg's baffled kids across the UK by renaming its popular Coco Pops cereal Choco Krispies. Sales of the product nosedived. A survey of one million people found that 92% preferred the old name, which Kellogg's promptly reinstated in May 1999.

But it seems the company didn't learn from its mistake. In the US, Kellogg's has sold a cereal called Cocoa Krispies since the 1950s. When it tried to change its name to Cocoa Rice Krispies in 2003, it didn't go down well and Kellogg's reverted to the original name in 2006. 

Tropicana, at the time a subsidiary of PepsiCo, pumped around $35 million into overhauling its Pure Premium packaging in 2009, the equivalent of $51 million (£40.2m) in today's money. Its decision to replace the image of a straw inside an orange with an image of juice in a glass might sound simple, but it soon became known as the 'Tropicana Crisis'.

Customers hated the new cartons and sales dropped by 20%. Tropicana eventually reverted back to the original packaging, but the debacle cost an additional $30 million ($44m/£35m today) in lost sales. 

Necco Wafers have been around since the US Civil War, and the chalk-like confection has a loyal customer base. In 2009, these faithful aficionados were horrified when the Necco Wafers parent company tweaked the recipe, softening the sweets with glycerine, axing its lime flavour, and switching to all-natural ingredients.

As a result, sales fell by 35%, and the original formula was reinstated in 2011.

In 2010, Frito-Lay learned that the road to hell is often paved with good intentions after it introduced a 100% compostable bag for its SunChips line of potato chips. There was just one catch. The biodegradable packaging was exceptionally noisy, with some customers describing its crinkles and crackles as “deafening".

Frito-Lay responded by pulling the offending bags from sale after 18 months.

In 2011, Netflix flirted with the idea of separating its DVD-by-mail operation from its streaming service, calling its spin-off business Qwikster. But customers were far from impressed, especially since it came with a 60% price increase.

According to the Yale School of Management, two million subscribers left Netflix and the stock price dropped in value by more than 75%. Mindful of alienating its user base, Netflix wasted no time abandoning Qwikster and refocused its energy on streaming.

In 2013, Breyers cut the milk content of its ice cream, a decision that forced the company to relabel its products as 'Frozen Dairy Desserts'. The change was met with a decidedly icy response from lovers of the brand.

In an effort to appease these customers, Breyer has since introduced some products with richer dairy content, which have the magic words 'ice cream' on their labelling.

Nestlé gave its long-established Milo chocolate malt recipe a healthy makeover in 2015, but the formula tweak didn't go down too well with the drink's fans.

After complaints that the new 'improved' version was less chocolatey, Nestlé reinstated its old formula in 2019. 

Patak's, one of the UK's most popular puveyors of Indian food, inflamed its curry fans in 2015 by tweaking the recipe of its lime pickle.

Angry customers took to social media to slate the new condiment, flooding the firm with complaints and leaving scathing reviews online. As you might expect, Patak's relented and brought back the original recipe in February 2016. 

Fans of Toblerone freaked out in 2016 when parent company Mondelez International increased the space between the Swiss chocolate bar's famous peaks. An example of shrinkflation, the change was made to decrease the weight of the product and keep prices down.

Mindful of the negative response, Mondelez reverted to the old shape in 2018 but increased the bar's price as a result.

Aussie food company Arnott's modified the recipe of its original Pizza Shapes in April 2016. The company was trying to give the snacks a healthy update. 

Despite its best intentions, customers were far from pleased and 30,000 people signed a Change.org petition for Arnott's to return to its original recipe. The company restored the flavour five months later. 

As though its original name wasn't long enough, I Can't Believe It's Not Butter! UK went all out in 2017 and rebranded as the even wordier I Can't Believe It's So Good... For Everything!

The new name was roundly mocked, and in 2019, the brand's parent company wisely decided to revert to the old name.

Keen to capitalise on the body inclusivity movement, Dove UK brought out limited-edition 'body positive' packaging for its body wash line in 2017.

Parent company Unilever hoped the new bottles, which supposedly represented diverse body types, would empower its customers. Instead, users of the brand felt patronised and insulted, taking to social media to ridicule the packaging.

The Coca-Cola Company must rue the day in April 1985 when it decided to tamper with the formula of its flagship drink. After blind tests found that people preferred the sweeter taste of Pepsi, executives decided to increase the sweetness of Coke.

But long-time fans of the beverage were up in arms. Sales plummeted, particularly in America's southern states, and Coca-Cola reintroduced the original formula just three months after the launch of the much-derided 'New Coke'.

British retailer Marks & Spencer's popular full-brief knickers are not to be messed with if the reaction to the company's ill-fated tweaks in 2018 is anything to go by.

The high-street stalwart was inundated with complaints after altering the seam on its classic 'granny pants' and was forced to backtrack on the notorious redesign. 

After battling plans to discontinue the brand in 2000, UK Salad Cream fans sprung into action again when Heinz announced it would rename the sauce 'Sandwich Cream' in June 2018.

A tidal wave of complaints followed, with research showing that 87% of customers were against the name change. Thankfully, Heinz caved and abandoned the rebrand in September of the same year. 

From Starbucks to Sony, discover the famous brands that changed their names

Updated by Matt Bradfield