In the derivatives world, there's a saying for trying to bet against highly unlikely events with catastrophic risk for small gains: "picking up nickels in front of a steamroller." The issue is when you pick up enough nickels and watch for the steamrollers vigilantly first few times, you grow complacent and think that you are the master of nickel pickers and steamrollers are slow mofo's. You try to pick more nickels and linger longer in front of incoming steamrollers.

See debacle of Long Term Capital Management. Options trader take profit/loss as soon as a humble target is hit. It's as in life, the biggest loss is the complete loss of your physical capital which takes you out permanently of the game. Gamblers focus on the potential profits and get high on how their luck evaded fate in one nick of time, traders focus on preservation of capital.