During the transition from a planned economy to a socialist market economy, China introduced individual accounts and established a basic pension insurance system for employees that combines social pooling with individual accounts. The pursuit of incentives and efficiency is the core concept of this decision. In theory, the incentive mechanism for basic pension insurance is mainly achieved through institutional structure and operational mechanisms. The incentive intensity of the current system is already high enough and the incentive width is wide enough, but more than 20 years of practice have proven that the incentive effect of the system has not been demonstrated, and the constraint force is clearly insufficient. This is not only related to the subjective reasons of individual rationality but also deeply influenced by the objective conditions of China's economic and social development stage. From international experience, when public pension funds are in crisis, abandoning parameter reform plans and choosing privatization may seem like a shortcut, but in reality, it is a wrong path. Incentives are not the only goal, or even the main goal, of the development of the basic pension insurance system. The incentive effect that individual accounts can achieve can also be achieved through social insurance, and the key lies in institutional design rather than institutional models. Due to the fact that strengthening incentives inevitably undermines fairness, a mandatory social insurance system should not overly emphasize incentive mechanisms, but should prioritize constraint mechanisms that reflect legal obligations. From a practical perspective in China, the trend factors of population ageing, historical factors of introducing individual accounts, and institutional factors with insufficient parameter constraints jointly lead to financial unsustainable risks in the operation of the system, and also result in an 

imbalance in the structure of the multi-pillar pension system. The prominent problem of China's basic pension insurance system is not insufficient incentives but insufficient constraints. The tools for parameter reform are far from exhausted, and it is not advisable to use the name of "incentives" to expand the size of individual accounts. In terms of reform suggestions, the basic pension insurance system should separate social pooling and individual accounts and return to the pay-as-you-go model; Strengthen legal obligations and constraint mechanisms, and achieve moderate incentive functions by improving the pension calculation methods; On the basis of improving the basic pension insurance system, we will orderly develop voluntary cumulative pension plans.