Complex sentence: The cognitive bias of illusory superiority derives from the metacognitive inability of low-ability persons to recognize their own ineptitude; without the self-awareness of metacognition, low-ability people cannot objectively evaluate their actual competence or incompetence.
Split into simpler sentences: The cognitive bias of illusory superiority derives from the metacognitive inability of low-ability persons to recognize their own ineptitude. Without the self-awareness of metacognition, low-ability people cannot objectively evaluate their actual competence or incompetence.