Among the top 0.1% of startups based on growth in their first five years, we find that the founders started their companies, on average, when they were 45 years old. Why might this be? Although there are many other factors that may explain the age advantage in entrepreneurship, we found that work experience plays a critical role. Relative to founders with no relevant experience, those with at least three years of prior work experience in the same narrow industry as their startup were 85% more likely to launch a highly successful startup.
https://hbr.org/2018/07/research-the-average-age-of-a-succes...