2 Kings 21:9, 16

But the people didn’t listen. Manasseh led them off the beaten path into practices of evil even exceeding the evil of the pagan nations that GOD had earlier destroyed.

The final word on Manasseh was that he was an indiscriminate murderer. He drenched Jerusalem with the innocent blood of his victims. That’s on top of all the sins in which he involved his people. As far as GOD was concerned, he’d turned them into a nation of sinners.