Poor people have it. Rich people need it. It can make you or break you.

 Steel is hardened by being exposed to the roaring fires of a furnace and then cooled down, and so too is the human spirit hardened by it. The rich and privileged lack it and often become spoiled, with a warped view of reality and a childish ignorance of the ways of the world. However, if a person faces numerous hardships without the ability to cool down and recover, his or her spirit can be broken or they can become bitter and jaded. You need to live through some tough times to get respect for life and hone those survival skills, but remember that there are also those whose hardships have taken them to a dangerous place—beware of such people. That elusive quality is called adversity.