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Things are bound to go wrong sometime, right?

In spite of intense product testing, millions of products are yanked off US shelves every year when manufacturers discover their products are not working out quite the way they should do. Some of the products turn out to be dangerous, some even lethal, and some are just downright weird. Here are five of the craziest reasons for product recalls we at Fueled have come across.

The Fitbit tracker seemed like an ideal product.

It's an activity tracker designed to help people live healthier lives  by allowing them to see evidence of calories burned, steps walked, distance travelled and sleep patterns.

A flurry of complaints of skin rashes, welts and even blisters has led the San Francisco firm to recall all the new tracker bracelets they've distributed. 1.7% of users reported some irritation, perhaps reacting to the nickel used in the tracker or to the materials used in the strap.

The recall is costly, but even more worrying is the potential cost of repairing the damage to their reputation, never mind the sufferers' skin.

2. Chemical Burns

Flip-flops are cheap and easy and perfect for strolling around the summer. Usually the only problem is getting your feet dirty if you're walking around a city all day. Or so you thought.

Back in 2007, things got a little more risky. While usually made from plastic, rubber or some combination thereof, a Chinese company decided to make them from benzene, resulting in chemical burns across the feet of some of the people who bought them.

Walmart eventually removed them from their shelves.

3. A Cop Shot Himself

Usually when you remove a gun from its holster, you expect to still be in control of whether or not you actually shoot the thing.

 In this case, there was a manufacturing error with the retention strap of the Kydex belt holsters made by Michaels in Oregon. As a result, when putting the gun back into its holster, it was possible the gun would unexpectedly fire. On at least one occasion, a cop shot himself in the leg.

Thousands of holsters ended up being recalled.

4. Added Bacteria

Anti-bacterial hand sanitizer is a great cash cow but one company, Clarcon, went out of their way to alter the usually easy formula (rubbing alcohol plus thickening agent plus fragrance) to make a revolutionary 'no alcohol' version.

In the process, they managed to get dangerous levels of disease-causing bacteria into the bottles. They marketed the product as being great for open wounds so on discovery of such dangerously high numbers of bacteria inside they were very hastily recalled.

5. Chocolate Worms

Bugs are indeed a food source in many parts of the world. When knowingly and willfully consumed, can even be a treat to intrepid culinary adventurers.

It's not what you expect to find in your box of luxury chocolates though.

Unfortunately, several unlucky customers found these in their boxes in 2007. They unwrapped their counterfeit luxury chocolates made in China to discover larvae worm from a common moth crawling all over their chocolate treat!

A good reason not to buy counterfeit goods if ever there was one!

Author Bio   
This article is written by Ilan Nass from Fueled, an award winning mobile app design and development house based in New York and London.