When researchers gave a bunch of monkeys an apple, they were happy. When the researchers gave a different bunch of monkeys two apples, they were happy, but not much more so than the first bunch. But, when the researchers took one of the apples away from the second bunch, they had some seriously unhappy monkeys on their hands. Every monkey ended up with one apple, but the second group had experienced a loss! They didn’t take it very well.
Source: Markets