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Named by Time magazine as one of the best inventions of 2012, Google Glass consisted of a pair of hi-tech specs with a heads-up display on which information scrolled across the eyeline of the user, all activated by voice commands. A passion project of Google co-founder Sergey Brin, Google Glass also allowed users to take photos and record video footage.

As former Â鶹Éç technology correspondent Rory Cellan Jones says: "The basic idea of a new way of getting information is a powerful one." However, three years after its snazzy launch in 2012, Google Glass was canned.

The product was created amid a clamour for 'wearable computing', something that was 'always on'. However, while the utility and image of Google Glass were attractive, the privacy concerns around the wearer being able to film and photograph others without being noticed proved to be its undoing. "I just cannot envisage us ever living in a time where we're all comfortable with somebody wearing a pair of glasses that might have a camera in it," says Sean.

But was this the main reason why Google Glass failed? Find out by listening here.

Discovered by scientists at Procter & Gamble in the 1960s, Olestra was a fat substitute that wasn't absorbed in the body. Tested in cakes, doughnuts and ice cream, it reduced calorie count by up to 50%.

It seemed like a breakthrough for dieters, but the feedback on Olestra's subsequent trials was disastrous – and rather revolting. "They were all the same complaint," explains food scientist Peter Berry Ottaway, "anal leaking coming out of the rectum without any control."

The product seemed to have reached a dead end, but Proctor & Gamble reformulated it and focused on savoury snacks, and, in 1990, applied to the US Food and Drug Administration (FDA) for approval. The approval came six years later, but products using Olestra had to declare that they could cause abdominal cramping and loose stools.

Consumers were initially undeterred and better medical results about side-effects started to surface, but a vociferous and ongoing campaign against Olestra’s use by CSPI (the Center for Science in the Public Interest) and the product becoming the butt of jokes by US TV comedians meant Olestra was dead in the water.

But it’s a fight that Sam White thinks they should have persevered with. "It really was a PR battle," she says, "and I would have come out fighting."

Find out whether Olestra could have avoided a race to the bottom by listening here.

Launched in 1985 in Dallas, Texas, the video store Blockbuster lived up to its name for almost 30 years. At its peak, in 2004, it reached 9,000 stores globally, 84,000 employees and nearly $5.9 billion in revenue.

A Blockbuster Video store in Tottenham Hale, London, in 2002.

Guardian film and TV writer Stuart Heritage recalls its arrival on the scene as "equivalent of eating at Wimpy and then going to McDonald's; everything was a bit better branded and a bit lighter."

In 2000, Blockbuster passed on buying Netflix. While this seems like the defining downfall moment, and it was certainly an enormous mistake, Blockbuster had been looking at offering their own streaming services. This focus switched after 2005 when media giant Viacom sold Blockbuster from their portfolio, saddling it with debts. A subsequent buyout from 'activist investors' steered the company away from innovation and towards consolidation.

Of the Blockbuster psyche, Sam White observes: "It's very easy for people to be intoxicated with success and to start to believe that nothing will ever get in the way, but my general experience of life is that that is just not the case."

Was mindset the only reason Blockbuster ended up on the cutting room floor? Find out more here.

Launched by computer engineer Julie Pankhurst and her husband Steve in July 2000, the Friends Reunited website helped people trace their old school friends. A forerunner to social media and a market-leader in nostalgia, the site's initial growth was extremely modest.

Sean Farrington tries out a Sinclair C5 on Bournemouth's seafront.

But after the site was mentioned on Radio 2's Steve Wright in the Afternoon show in January 2001, Friends Reunited gained traction, and, by the end of 2002, had attracted 8 million users. The inevitable transition from free to paid subscription didn't dampen enthusiasm, nor did a backlash of bad press, fuelled by stories of old school friends having affairs and teachers being slandered.

Friends Reunited went unscathed until its sale to ITV in 2005 for £175 million. The acquisition was a flop, and, in 2009, ITV got rid of the site for a mere £25 million. The channel had overpaid for a centrepiece of their digital strategy despite, as Sam puts it, being "a business that culturally just was not in the right place."

Despite its drastic change of fortunes, Sam believes that Friends Reunited "could have taken on the Facebooks of this world."

Find out more about why Friends Reunited fell out of favour by listening here.

Sinclair C5

Marketed as an electric car but resembling a go-kart, the Sinclair C5 was rolled out to the public in January 1985. The brainchild of Sir Clive Sinclair, the celebrated inventor, the C5 seemed like it could have joined the first pocket calculator and home microcomputer as another Sinclair success story – it didn't require road tax or a licence and was suitable for anyone aged 14 and up to drive.

However, things went downhill – literally – from the off, with journalists at the launch taking them for unauthorised test drives and finding that its batteries lost power quickly in the face of low temperatures and hilly terrains. There were road safety concerns voiced in some quarters too.

"Clive didn't believe in market research," explains Barrie Wills, the former MD of Sinclair Vehicles, offering a clue to why the C5 went off-road. Ultimately, however, Sam feels that it all came down to "misaligned expectations at every step of the way."

Hear more about the obstacles that the C5 just couldn't get over by listening here.