The Goalpost

You are seeking success, so you need a goal to define success. Bad news: the goal post keeps moving.

You can use soccer, American football, hockey, or several other sports as analogies. Your choice. In any case,

   - The world is shrinking, so as soon as you prove excellence, someone
      else will come along and do it cheaper.

   - Expectations always grow, so as soon as you prove excellence, then
     excellence becomes the new normal.