Why don't many factories directly recruit ordinary workers?

Why do many factories not directly recruit ordinary workers, but have to send labor services to the company? Direct recruitment faces many disadvantages, and sending it directly to the labor dispatch unit can save a lot of unnecessary ones. For example: 1, industrial injury, especially for manufacturing industry, is inevitable. In the event of a major accident, enterprises still have to bear a lot of work-related injury expenses. If the work-related injury is identified as 1-6, the enterprise shall pay the disability subsidy and employment subsidy in one lump sum in accordance with the Regulations on Work-related Injury Insurance, and part of the expenses shall be paid monthly. Labor dispatch employees are labor contracts signed with dispatching units. 2. Save the cost and save the labor cost of the employing enterprise. Direct job fairs in enterprises consume a lot of recruitment time. The establishment of the human resources department, the cooperation of school recruitment, social recruitment, agency recruitment and recruitment websites, recruitment also requires interviews, entry, training, resignation, and even subsequent labor disputes. It takes a lot of people and time to complete. For example, when the job is transferred to a labor dispatch unit, the employer only needs to sort out the needs and conditions of the employees and send them to the dispatch unit.