Joe Maddon's book biases me here. Maddon suggests that stats are critical. He fully integrated them into his thinking. But Maddon dug more deeply into years of understanding the game, his players strengths, what players were dealing with at home, relationships with players, and years of similar events which he calls his intuition, his GUT. These aren't necessarily a conscious awareness.
It is a complicated algorithm run in the manager's subconscious and must be integrated and trusted in making conscious decisions.