The Dunning-Kruger effect is a cognitive bias in which individuals with low ability tend to overestimate their competence, while highly competent individuals may underestimate their abilities. This phenomenon arises because those lacking in skill are unable to recognize their own incompetence or accurately assess the skill level of others. They lack metacognitive awareness—the capacity to reflect on the limits of their own knowledge or expertise. Conversely, high performers often mistakenly assume that tasks they find easy are equally easy for others, leading them to undervalue their relative superiority. At its core, the effect reveals that the unskilled experience illusory superiority due to distorted self-perception, while the skilled underestimate themselves due to inaccurate assumptions about others.