Why are China citizens prevented from leaving the country with private passports to work in Singapore?

Because of Singapore's policy, China citizens who work in Singapore with private passports are prohibited from leaving the country. According to the news released this week by the National Immigration Bureau of China, it is necessary to strictly implement the strict exit-entry policy, strictly limit China citizens' unnecessary exit activities, and strictly examine and issue exit-entry documents. Because the development of Singapore depends largely on foreign talents, such a policy is to keep these talents and let them continue to work in the local area, so it will prevent China citizens who come to work in Singapore with personal passports from leaving the country.