The reasons are as follows:

1. The internal management system is not good, which makes the brain drain serious.

2. The old employees are unfamiliar with the company's business and can't adapt to the company's rhythm, so they choose to leave.

3. The company's business volume is small, and employees can't be paid in time, so everyone chooses to leave.

4. The company's system is not perfect, so it can't provide corresponding benefits to employees in time, so it chooses to leave.