Many people attribute to the working of the law of karma the good luck, fortune or ill-luck that seems to have no specific root cause in the current lifetime. The argument goes that this is some kind of recompense or retribution for the good deeds or sins of a past lifetime. This argument, however, is too simplistic and boils down karma to some kind of mathematical justice-meting machinery across lifetimes, with the human judgment of “good” or “bad” acting as the “principle” upon which this karma supposedly operates.
Sri Aurobindo takes a more complex view of the matter: “There is indeed in our life a very large element of what we call luck or fortune, which baulks our effort of result or gives the prize without effort or to an inferior energy: the secret cause of these caprices of Destiny,–or causes, for the roots of Fortune may be manifold,–must be no doubt partly sought for in our hidden past; but it is difficult to accept the simple solution that good luck is a return for a forgotten virtuous action in a past life and bad luck a return for a sin or crime. If we see the rightous man suffering here, it is difficult to believe that this paragon of virtue was in the last life a scoundrel and is paying, even after his exemplary conversion by a new birth, for sins he then committed; nor, if the wicked triumphs, can we easily suppose that he was in his last life a saint who has suddenly taken a wrong turn but continues to receive a cash-return for his previous virtue. A total change of this kind between life and life is possible though not likely to be frequent, but to saddle the new opposite personality with the rewards or punishments of the old looks like a purposeless and purely mechanical procedure. This and many other difficulties arise, and the too simple logic of the correlation is not so strong as it claims to be; the idea of retribution of Karma as a compensation for the injustice of life and Nature is a feeble basis for the theory, for it puts forward a shallow and superficial human feeling and standard as the sense of the cosmic Law and is based on an unsound reasoning; there must be some other and stronger foundation for the law of Karma.”
In fact, it would not make sense when we have understood Karma to be the momentum and carrying out of the consequences of the movement of energy, as we would expect to see the positive actions of the saint continue to develop as the soul takes up its ongoing evolutionary progression, and similarly those wedded to desire and all kinds of vital impulsions would not necessarily enjoy the fruits of virtue in the next subsequent lifetime, but would likely be working out the attachments and residual results of that highly-focused and formed desire body of the past which impels itself onward until resolved.
Sri Aurobindo, The Life Divine, Book 2, Part 2, Chapter 22, Rebirth and Other Worlds; Karma, the Soul and Immortality