Suffering is a means of restoring a person to God.
There are many who will never awaken to holiness without some life crisis.
Just as it is interesting to observe the effects of what is considered "success."
Not only does success often bring a certain crassness and insensitivity, but it also brings a forgetting of how to be grateful.
–Rabbi Adin Steinsaltz
From "The Meaning of Sadness" in The Long Shorter Way by Rabbi Adin Steinsaltz