1) We die. We are fated to die. The best, the brightest, the strongest, the richest, the ablest--all die. No effort to prevent it is ultimately successful. We can no more outrun our fate than Oedipus can his.
2) The knowledge we need to make the right decision, on those occasions when such knowledge may be said to exist, is always attained after the decision has been made, when, right or wrong, it is too late.
3) The decision that leads to self knowledge--which can thus lead us to an understanding of, for example, the best way to spend one's life--is always different from the decision that leads to the best way to spend one's life. Does one choose to give one's life to art--forsaking job, family, security, reputation for the sake of art? Then one will always attribute one's failure to the market, to time, to history. On the other hand, should one choose to be an art historian, then one might come to the realization that one never could have been an artist--that one didn't have "the stuff." Enlightenment! One should have pursued science.