What Jeroboam did was sinful. And it caused Israel to sin. The people came to worship the statue at Bethel. They went all the way to Dan to worship the statue that was there.
When he tore Israel away from the house of David, they made Jeroboam son of Nebat their king. Jeroboam enticed Israel away from following the Lord and caused them to commit a great sin.
Yet Jehu was not careful to keep the law of the Lord, the God of Israel, with all his heart. He did not turn away from the sins of Jeroboam, which he had caused Israel to commit.