A difficult word to tie down. It means something different to almost every individual on the planet. And it means different things to the same person at different times.
But one thing is common for all. It is a mindset. The determination to do whatever it is that will give you the feeling of achievement.
Some people have more of it in life than others. Some people equate it only with financial gain. Others achieve everything they want in life without earning a penny.
What is the difference between the person who has gained this elusive quality and the one who has not?