The best case scenario for the Chiefs there would have been to continue running the ball until they could score with very little time remaining, hence the idea of not scoring immediately.
On the flip side, the Bengals couldn't afford to let the Chiefs run all the time out and score, with no chance to counter. In comes the idea to let them score, to at least give yourself a shot.
KC botched the play calling about as bad as you could in that sequence and Cincy's defense capitalized, keeping them out of the end zone.