It might seem to be obvious that the more experience we have, the more accurate the outcomes of our decision. People also say to get better you should practice more, even more specifically they say ‘Perfect practice makes perfect’. The problem is that perfect practice and experience aren’t the same things. Perfect practice (Eriksson's 10 000 hour rule) gives you expertise whereas general practice in a wide range of environments, with a wide range of people, over a long period of time gives you experience and it is this experience that helps you make better decisions in uncertain situations.
Decision making is informed by situation awareness: sensing data, creating an understanding of what is going on around us now and then projecting into the future what is likely to happen, and finally, executing on that to achieve goals or objectives.
Situation awareness is informed by sensory input, expectations, experience, training and abilities but it is limited. We are constantly filtering data, billions of bits of data, ditching the majority of it. We only pay active attention to those things that we perceive to be important and/or relevant. Something that could be summarised as DIPI. Dangerous. Important. Pleasurable. Interesting.