In other cases his self-deception can give him a big advantage. Trump has a great natural talent for creating narratives that a certain population wants to believe. Their own self deception creates a convenient self-serving reality. He creates The Big Lie, which is what this program is about.
But Trump also creates the medium lies and the little bitty lies, constantly. That's what the constant, "pathological lying" is all about. I mean he does his own hair and his own makeup, looks at himself in the mirror, and genuinely thinks, "Damn, I look good." He lies about big things, little things, things that have no consequence. It just pours our of him in an automatic process.