What does the push-pull theory mean among the reasons of urbanization development?

1. The push-pull theory in the cause of urbanization development means that labor migration is caused by the wage difference between the place where people move in and the place where they move out. Modern push-pull theory holds that in addition to higher income, the push-pull factors of migration include better jobs, better living conditions, better educational opportunities for themselves and their children, and better social environment.

2. In 1960s, American scholar Li Zhengdao put forward a systematic theory of population migration-"push-pull theory". For the first time, he divided the factors affecting migration into "thrust" and "pull". He thinks the former is a negative factor, because these factors prompt immigrants to leave their original place of residence; The latter is a positive factor, because these factors attract immigrants who want to improve their lives to move into new places of residence.