ELI5: Explain Like I'm 5

Self-serving bias

Self-serving bias is like when you want to believe things are true because it makes you feel happy or makes you look good. It's not really being honest. For example, some people like to say they got an A on a test because it makes them feel good, even if they actually got a B. It's tricky because people don't always realize they are doing it, but it's not the same as telling the truth.