Decision making is as much art as science. The goal, if we have one, is not to make perfect decisions but rather to make better decisions than average. To do this we require either good luck or better insight. And since luck isn’t really much of a plan, we should probably focus on better insight.
In most of life you can get a step ahead of others by going to the gym or the library, or even a better school. Yet, not many people will achieve the skills and superior insight necessary to be an above average thinker. And yet we live in a world that, if it rewards anything, it rewards better decisions; a result of a good thinking.
For me, the real difference is that first-level thinkers are those people that look for things that are simple, easy, and defendable. Second-level thinkers push harder and don’t accept the first conclusion. Second-level thinkers take into account things like, ‘What is the range of possible outcomes?’, ‘What’s the probability I’m right?’, ‘What’s the follow-on?’, ‘How could I be wrong?’.
This is where things get interesting. Extraordinary performance comes from being different, from having thought through the process differently. It must be that way.
But, it’s not enough to be different — you also need to be correct. Conventional thinking and behaviour is safe. But it guarantees mediocrity. After all, if your thoughts and behaviour are conventional, you’re likely to get conventional results. You need to know when your performance is likely to be improved by being unconventional. Only by doing something different,  and putting yourself  ‘out there’,  do you get to learn if you are doing it correctly.