This is for all the customer service reps who spend their days trying to make disgruntled customers happy: A study in the Journal of Marketing Research shows that people actually complain the most when they know they're wrong!

Researchers recruited volunteers to make smoothies. But the blenders they were given were defective so, it was impossible to actually make one. Half of the volunteers were told the blenders were on the fritz. While the rest were led to believe that the problem was their own fault.

When the researchers asked for feedback on the experiment, the results were surprising. The people who thought they were the cause of the problem were the most defensive and confrontational. And get this: Almost all of them blamed the blender – even though they were told it was working perfectly. But those who thought the blenders had malfunctioned were willing to accept at least some personal responsibility for the problem.

What’s going on here? Study coauthor Lee Dunn says that when people believe that they’re at fault, they shift blame to protect their egos.

So, if you’re shopping for a product and see a bad review, it might have less to do with a defective product, and more to do with the reviewer being all thumbs.

And if you’re a customer service rep well technically, the customer’s always right.  But knowing that the squeakiest wheel may really be complaining about their own shortcomings might make it easier to mentally shrug off rude callers.