EPI scores are positively correlated with a country's wealth, although after a point, increasing wealth yields diminishing returns. At every level of economic development, though, some countries outperform their peers while others lag. Some of the poorest countries in the world outperform some of the richest. In this regard, factors other than wealth, such as investments in human development, rule of law, and regulatory quality, are stronger predictors of environmental performance.

Wealth allows countries to make investments in the infrastructure