He owned slaves. Quite a lot of them. When he inherited them if he really believed that "all men are created equal and they are endowed by their Creator with certain unalienable rights" he should have freed them. He did not. He only freed a limited number in his life. That alone tells me the man had his flaws and failings. He failed to live up to his words. Monticello records indicate he owned over 600 slaves in his lifetime and sold some 110 to cover his mounting debts which were substantial at the time of his death. He denounced slavery but practiced it.
He had great ideas but was lousy at living up to them. He profited from the very thing he condemned. He was a flawed human.

