Capital deepening refers to the process of increasing the ratio of capital (physical capital, such as machinery, equipment, and infrastructure) to labor in the production process. After World War II, there was a significant increase in capital deepening in many countries, which was a major factor in the increased productivity of workers. This increase in capital deepening was the result of a combination of factors, including technological advancements, increased investment in machinery and equipment, and the availability of a more skilled labor force.