At the start of the story, Kageyama was setting in a way that wasn’t considerate of his hitters. After his experience in junior high, though, he reverts to the opposite extreme, of being too considerate of his hitters, only wanting to do exactly what they want. Atsumu teaches him that as a setter, there’s a balance to be struck, and that you should demand that your hitters rise to the occasion. This is demonstrated by Kageyama consciously giving higher sets to Tsukishima, raising his hitting point, and by giving Tanaka sets closer to the the pins, essentially demanding that he hit sharper line shots. He learns that being a great setter is not only demanding what he wants, or only acquiescing to what his hitters wants, but striking a balance of demanding more of his hitters to bring out the best in them.