This is a well known economic fact and points to why economic niches rapidly form monopolies. These monopolies, once entrenched, can never be dislodged thanks

This is a well known economic fact and points to why economic niches rapidly form monopolies. These monopolies, once entrenched, can never be dislodged thanks to their economies of scale. > The average lifespan of a company listed in the S&P 500 index of leading US companies has decreased by more than 50 years in the last century, from 67 years in the 1920s to just 15 years today, according to Professor Richard Foster from Yale University. Oh.