I was listening to a podcast on hidden brain and I have understood why we all have biases. When we judge ourselves we look inwards i.e. we look at our past experiences, our values, our memories, our goals and our motivations. Therefore we judge ourselves with a different yardstick than what we use to judge others. Because we judge other by their actions. We don't know why they do why they do. "When someone drives slower than us, they are an idiot, when they drive faster they are a maniac"