Why is the environmental pollution in China so heavy, while the air quality in developed countries is better? Their car exhaust, the factory is no less than ours?

Backward technology and poor management; Low awareness of environmental protection, entrepreneurs did not bear the corresponding social responsibility; Lack of supervision system; Relevant laws are not perfect, and they shall be implemented according to law; Emission standards, the amount of fines for illegal discharge is low; The development of green industry is insufficient and the price of green products is high; The infrastructure for treating the three wastes can't keep up with the growth rate of the three wastes.