The answer is rather simple analysis and insight.
•They are insightful thinkers who take time regularly to asses and analyse the situation and take the next step of action.
•It's not like everyday people don't do it. But smart people do it most of the time.
•The reason they don't get analysis paralysis is they have clear priorities.
• They too get decision fatigue but out of sheer practice of their proper smartness they have built ways for bouncing back and recovery from decision fatigue quickly.
For example albert Einstein used to go for boating in nature regularly to recharge.