9 Costliest Mistakes

1Ronald Wayne Gives Up Stake in Apple, Losing Out On $22 Billion

Wozniak, Jobs... and Wayne? That's right, there was a THIRD founder of Apple computers that you've never heard of. That's because Ronald Wayne gave back his stake in the multi-billion dollar company back in its earliest days in 1976. Woz and Jobs each had 45 percent shares and Wayne, who was their elder, had 10 percent. He was supposed to be the “adult-in-chief” and settle any disputes between the other two, but Wayne felt the pair were too young and inexperienced and feared that the company would go under and he'd be liable. Less than two weeks after signing the agreement, he cashed out for $2,300. Oops!

2Temporary Cap on Gas Valve Causes Oil Rig Explosion, Costs $3.4 Billion

The Piper Alpha disaster happened in July 1988 and is still the one of the costliest and deadliest series of mistakes, perhaps ever.

First, gas compression units were installed next to the control room. Next, the rig was kept in service during upgrade and maintenance work. Finally, one of 100 safety valves had been covered with a temporary cap. When a technician, who was not informed of the maintenance, pressed the start button the whole thing went KA-BOOM, killing 167 workers and costing $3.4 billion in damages. (While Deepwater Horizon ended up costing more in damages, its causes are more complex.)

3Japanese Broker Error Costs $225 Million

In 2005, a careless Japanese broker meant to sell just one share of J-Com, a recruiting company, for 610,000 yen ($5041 US) but instead sold 610,000 shares at 1 yen. Even though the trade was larger than their outstanding shares and the broker tried to cancel 3 times, it still went through. The result? Chaos on the Tokyo Stock Exchange and a loss of $225 million for Mizuho Securities Co., wiping out its profits for the previous fiscal year.

4NASA Pounds vs. Newtons Snafu Loses $125 Million Satellite

It's the little things that make a difference: in this case, the difference between the metric system and the American system. The software engineers wrote the program for this Mars Orbiter to use pounds of force, but NASA assumed this calculation had been converted to newtons for space; it hadn't. When the satellite was launched, there were many warning signs, including a need to make dozens of adjustments during flight and the Orbiter ended up being destroyed when it flew too low in the Martian atmosphere. NASA said this became a textbook lesson in communication.

5Hoover Offers Free Flights, Sucks Up $74 Million

In 1992, the British arm of Hoover had a surplus of washing machines and vacuums, so they devised a promotional scheme to get rid of them: buy 100 Pounds worth of merch and get a 2 free round-trip tickets to anywhere in Europe or the US. The problem was these airline tickets were many more times expensive than than Hoover's "sucky" products. The company was caught off guard by the overwhelming demand – some 200,000 people ordered Hoover's cheapest vacuum at 120 Pounds and the company had to pay workers overtime to keep up with the orders. Hoover was soon in the hole for £30 million ($74 Million) to book all the promised flights. Several top executives lost their jobs and the European unit was sold to a rival appliance company.

6French Order Trains Too Big – Have to Spend $68 Million Adjusting Platform

French rail operator SNCF has a big bill on its hands, thanks to a lack of oversight. They were sent the measurements of railway platforms from RFF – a separate bureaucracy that run the trains in France – and SNCF failed to check to verify if these numbers were accurate. It turned out they were a few centimeters short, resulting ordering trains that were too wide to fit. The French Minister called it a “comic drama” and 1,300 platforms will have to be adjusted to the tune of €50 million ($68 million).

7Names, IDs of 2.2 Million Military Personnel on Stolen Laptop, Costing $20 Million

In 2006, an analyst for the U.S. Government was allowed to take home a laptop with sensitive information about military personnel. Big mistake, as the laptop was stolen. It turns out not only was this data unencrypted, but it contained 2.2 million names, Social Security numbers and birthdays of both active and retired persons.

A veteran's group sued for $26 billion, but the Department of Veterans Affairs eventually settled in 2009 for a lesser-but-still-expensive $20 million.

8Phone Book “Erotic” Misprint Costs Yellow Pages $10 Million

This mistake is funny, but not to Gloria Quinan of Banner Travel Services, who placed an ad in the Yellow Pages (‘memba them?) in 1988, expecting it to read “Exotic Travel Services.” Instead, a typo made it read “Erotic Travel Services,” causing a flurry of inappropriate phone calls, and a loss of 80% of her business. Quinan successfully sued for $10 million for “mental anguish” and “physical distress.”

9Extra Comma in Contract Costs Co. $888,000

Artist's rendering of the culprit

Punctuation, people, punctuation. An extra comma in a contract between two Canadian companies was used as a way to make it null-and-void.

The agreement between telecom giant Aliant to string cable lines for Rogers Communications at $9.60 a pole stated this: “shall continue in force for a period of five years from the date it is made, and thereafter for successive five year terms, unless and until terminated by one year prior notice in writing by either party.” Aliant said the second comma in the sentence meant they could cancel with one years' notice, while Rogers insisted the contract was meant to last five. Lawyers for Aliant called it “a basic rule of punctuation” and won in court. Rogers was on the hook for an additional $1 million Canadian ($888,000 US).