Albert Barnes Commentary 2 Kings 10:29

"Howbeit from the sins of Jeroboam the son of Nebat, wherewith he made Israel to sin, Jehu departed not from after them, [to wit], the golden calves that were in Beth-el, and that were in Dan." — 2 Kings 10:29 (ASV)

The thought of abolishing the calf-worship had probably never occurred to Jehu. He had enough religious feeling and patriotism to detest the utterly debasing Astarte worship, but the pure worship of Yahweh was altogether beyond and above him.