It's a much longer season. There are many more ups and downs. You don't want your team too high after a big win or too low after a disappointing loss. This is not an easy task. You can't completely protect players from the hype that surrounds big games.
Coaches usually have to downplay rivalry games and emotional wins and losses.
Conversely, getting players ready to play against opponents with lesser talent may take a little emotional prodding. It's not an exact science by any stretch of the imagination. It's more like a unique form of art. A great coach knows how and when to push the right buttons to make his team go. A coach has to handle a lot of responsibilities in a program and the psyche of his team may be the most important.