Dense population.
In big cities, the population is very dense and the competitiveness is very high. Big cities have good medical conditions and good educational resources, and everyone will choose to come to big cities because of these resources. So the population is very large, and when there are many people, the pressure will be great, because you can only live in this big city if you keep moving forward and working hard. If you don't work hard, you may be squeezed by others. So living in a big city is very stressful.
Prices in big cities are very high.
Now many young people will choose to work hard in big cities. Because big cities have better resources and better jobs, many young people will go to big cities. Although wages are high in big cities, prices are also high. Prices are rising, but wages are not increasing at the same time, so the pressure of life is very great. Moreover, in big cities, people are basically working and have little leisure time, so the pressure is getting bigger and bigger.
Life in big cities is fast and house prices are high.
Many people choose to buy a house in a big city, and there is great pressure to take a house mortgage every month. They not only have to pay the mortgage, but also bear the expenses of their families, as well as the expenses of their children going to school and supporting the elderly. The price is also very high, and their income has not increased by the same amount, so the pressure of life is very great. Moreover, the pace of life in big cities is fast. Most of the time, they are working hard, devoting themselves to their work and working non-stop every day.