Under duress, and having experienced a shattering blow of some kind, humans often ascribe the cause to karma. There is bad karma and good karma and this explains everything, or so they hope. Could it be that life is so terribly unpredictable? Why would a benign God throw them into such a situation, create such an erratic world? Yes and no, there is karma. Karma is at play where the human causes the situation in some manner, by their prior actions in this lifetime. Karma is not at play when the life situation occurs because of acts of nature or the actions of other humans not directly involved in the situation at hand. We will give examples.
Karma. A man is greedy, always seeking to maximize the goods that he can call his own. Materialistic. In the main he succeeds in becoming a man of means, and secretly gloats over his ability to charm or manipulate others so that he succeeds. Then one day he finds himself a pauper, having been outdone by one with greater charm or manipulation skills. Is this karma? It is indeed, as the man brought this down on himself by amassing goods and bragging about. He essentially placed a sign where everyone could see, saying come steal from me. It would also be karma if a former business partner, having been left bereft and financially devastated due to the actions of the greedy one, arranged for the greedy one to have marital troubles. Where one's trouble can be traced directly to one's own actions in this lifetime, that is karma.
Not karma. A woman desires children, and in due course marries and becomes pregnant. Through a throw of nature's dice, one of her conceptions has an extra chromosome, and is a mongoloid, retarded. Friends point out that she was not a scrupulous housekeeper, or perhaps was torn between her career and family duties, and that her misfortune is karma as now she must stay home and tend to the new youngster, who needs constant care. Another example is a car accident, where one is driving down the highway and, rounding the curve, finds themselves head on with a drunken driver. Did the victim cause this accident somehow? It was simply a matter of time and place, a throw of the dice. These situations do not involve karma, not even as retribution from a former lifetime, which never occurs. Each incarnation is truly a fresh start.