depends what are you doing contemporary. decision are affected by numerous factor, like time, circumstances, family background, peer pressure, ambition, poverty, social status etc. specifically, in my case i look into the bigger picture of how the job i am going to select will serve my ambition along with my family and clan needs. similarly, am i of a little help to humanity or am i contributing something positive for the society, if the answer is yes, then i wont look back over the decision i made. as mentioned above those factors were kept in mind while choosing or making the decision. however, if things does not go as, i or you planned then the lesson is learnt of not going to make same mistakes again.