Això ho explicava detalladament Bret Stephens en un article imprescindible al Wall Street Journal titulat "Com Milton Friedman va salvar Xile":
It's not by chance that Chileans were living in houses of brick—and Haitians in houses of straw—when the wolf arrived to try to blow them down. In 1973, the year the proto-Chavista government of Salvador Allende was overthrown by Gen. Augusto Pinochet, Chile was an economic shambles. Inflation topped out at an annual rate of 1000%, foreign-currency reserves were totally depleted, and per capita GDP was roughly that of Peru and well below Argentina's.
What Chile did have was intellectual capital, thanks to an exchange program between its Catholic University and the economics department of the University of Chicago, then Friedman's academic home. Even before the 1973 coup, several of Chile's "Chicago Boys" had drafted a set of policy proposals which amounted to an off-the-shelf recipe for economic liberalization: sharp reductions to government spending and the money supply; privatization of state-owned companies; the elimination of obstacles to free enterprise and foreign investment, and so on.
(...)
As for Chile, Pinochet appointed a succession of Chicago Boys to senior economic posts. By 1990, the year he ceded power, per capita GDP had risen by 40% (in 2005 dollars) even as Peru and Argentina stagnated. Pinochet's democratic successors—all of them nominally left-of-center—only deepened the liberalization drive. Result: Chileans have become South America's richest people. They have the continent's lowest level of corruption, the lowest infant-mortality rate, and the lowest number of people living below the poverty line.
Chile also has some of the world's strictest building codes. That makes sense for a country that straddles two massive tectonic plates. But having codes is one thing, enforcing them is another. The quality and consistency of enforcement is typically correlated to the wealth of nations. The poorer the country, the likelier people are to scrimp on rebar, or use poor quality concrete, or lie about compliance. In the Sichuan earthquake of 2008, thousands of children were buried under schools also built according to code.
Un resum en castellà, aquí.