YTO Express, Zhang's employer and one of China's largest delivery companies, requires early delivery packages to be delivered before 2 o' clock pm. If there are late deliveries, Zhang will be fined 100 yuan, almost his daily wages. And if he loses a package, he needs to pay the full price.

To keep customers happy, the company also launched night delivery services, which require delivery men to work after 7 o'clock in the evening.

A branch manager of YTO Express surnamed Zhang (not related) said that delivery jobs have become the first choice for migrant workers looking to work in Beijing.

To retain workers, many delivery companies now provide accommodation and meals. "Two years ago, we only got scooters. Now we have more delivery trucks and electric tricycles, but the turnover remains high," said the manager.

Zhang Shuai plans to contract for a delivery service in the future and work on his own. "It is much more profitable to open a new service center and employ others to make deliveries, but before that, I need to make enough money for the investment."