Why is Xi's special account for flexible employees social security or normal insurance?

The social security paid by flexible employees is essentially employee social security. Different from employees' social security, there are only two insurances: pension and medical insurance, and the social security expenses are borne by individuals. However, the benefits enjoyed are the same as employee social security, and you can choose to pay according to the local salary base, which is very flexible. Although the contribution ratio is slightly different, the employees with the same contribution base who are flexible in employment receive the pension after retirement and the employees who retire from the unit are exactly the same.