First the depressing one: All the people around you either looking or acting strange (in a bad way) are actually trying to do their best. Now imagine who they really are when no one is around looking.
Challenging one: most of the important things in life are non-linear and hence the beauty of life lies on its unpredictability. The amount of effort you put into something is not proportional to your success. Split-second decisions may have an impact on your entire life (think about that quick moment when you decided to accept a job offer or decided to get married).