The Sting of Losing

Imagine walking down the street and finding a crisp $100 bill. You're thrilled. Now imagine reaching into your pocket and realizing you lost a $100 bill. You're devastated. But psychologically, the pain of losing that money feels about twice as intense as the joy of finding it.

This cognitive bias is called Loss Aversion. Humans are far more motivated to avoid losing something than they are to gain something of equal value.