To be grateful for one's blessings when all is well is no task; but to be grateful for the spiritual good we possess in the face of some physical problem that has been of long duration may put our faithfulness to the test.
Have you met people who believe that to be mature they must be allowed to do whatever they want, and then if it turns out to be wrong, well, they've just chalked up one more experience?
Those of us who recall anecdotes of World War II vintage may remember the one about the captive laborers in an occupied country who were searched each time they left the mines.