Drawing on social science, psychology, sociology, mathematics, economics, anthropology, neuroscience, and creativity, marketers have been coming up with all kinds of ideas to convince you that you not only need their product in your life but also that you’re getting an amazing deal if you buy more of their product instead of their competitor’s.

Coupons. Referral programs. Rewards clubs. Warehouse clubs. Loyalty cards. Buy five, get one free. One Day Only Sale! The list of marketing and promotion schemes that we’ve all come to know and expect in our normal everyday lives is endless. It’s nothing new. T-post has even experimented with a few of these.

But not all marketing ideas go as planned. 

The McDonald’s Happy Meal, a children’s meal packaged in a box with a toy. Good marketing idea. That is until this year when a New Zealand franchise accidentally replaced the sold-out toys with condoms. 

In the U.S., Domino's Pizza’s created a recession-proof promotion whereby anyone who typed in “bailout” on the order page would get a free pizza. Only problem was that the promotion hadn’t been approved yet, the code leaked out, and over 11,000 people demanded free pizza. Despite the “computer error”, Domino’s honored the giveaway anyway. 

In the Philippines, Pepsi offered 1 million pesos to anyone who got a bottle cap with the number 349 printed on it. Too bad there were half a million bottle caps printed with 349, which would have cost Pepsi 18 billion dollars. Bottling plants were attacked by angry contestants. Many executives had to leave the country. And Pepsi ended up awarding each winner $19, turning the promotion into a mere 10 million dollar mistake.