The Leverkusen team was not very strong. We do not see any star players in Leverkusen. On the other hand , Real Madrid has a lot of star players in their squad. And it's difficult to control so many star players. Also, a big club like Real Madrid will definitely play to secure both the Champions League and La Liga titles. Xabi Alonso has never faced such a big challenge in the past. So I think the chances of him succeeding in his first season are a little low. But Xabi Alonso is very talented. He will do his best to secure the La Liga title this season.
Having a number of talented players at a good level should make it much easier for a coach to achieve success because all that is needed is to control each player's ego so they can work collectively. This is where firmness and discipline are needed so that players can follow the coach's instructions in an orderly manner. Several previous coaches have successfully managed Real Madrid, and Xabi Alonso should be able to follow in their footsteps. It was different when he was managing Leverkusen because Xabi Alonso's role was very big in motivating his players to be able to play at a better level and of course the Champions League was different so it would not be so easy for Xabi Alonso to achieve success in a short time.