The Wheel of Fortune stands for an experience which every human being makes sooner or later: There are so many things we cannot influence. Blows of fate happen to us "just like that", imperatives force us onto certain paths, lovingly and carefully prepared plans are baffled. We are happy, our needs are met, we feel safe - and suddenly the Wheel turns and we fall very deep.
The Wheel of fortune tells us to learn to deal with the insecurities and necessities, the ups and downs of life in an acitve, positive way. If we can see and treat defeats, blows of fate, and suffering, as a source of learning, of understanding, and of wisdom, we won't feel at fate's mercy anymore. If we are conscious that good times are a gift and that bad times might come soon, we will enjoy and cherish the good times much more. If we don't learn to productively deal with the fateful, the coincidental, we will soon resign, develop fatalistic ideas and live in constant fear.