That is a decision which takes a lot of courage from Zidane's part. But now he left Madrid as a three consecutive Champions League winner meaning a football HERO!
and it is crazy how this was his first major coaching experience and managed to reach those levels in a very short time period. We will need to wait a very long time to see anyone else do this heroics again.
All I can say now is when the hardest period for him will begin. He was able to win titles with the best club in the world with great players, but a true great coach rises once he is able to bring the underdogs to the top of the world. Now the the question is will he be able to achieve this?