Confirmation bias is a cognitive phenomenon where individuals tend to overlook information that contradicts their beliefs while favoring data that supports them. This bias can be particularly tricky as it's often unnoticed, leading to skewed perceptions and judgments. For example, a scout might form a strong opinion about an athlete and then selectively gather evidence that reinforces that view, disregarding any contrary evidence.

This concept highlights a fundamental flaw in human reasoning, as it can significantly impact decision-making processes across various fields, including sports, science, and everyday life. Michael Lewis, in "The Undoing Project," illustrates how deep-seated biases can shape our understanding and beliefs, emphasizing the importance of awareness in overcoming these mental traps.