The greatest achievement of venture capital is that it can realize the direct combination of knowledge, ideas and capital, so that new knowledge and new ideas can quickly realize their value, transform into real productive forces and promote the upgrading of industrial structure, and the play of this role is inseparable from the successful withdrawal of venture capital.

the so-called "exit mechanism", or "export", refers to the venture capital institution's transformation of the invested capital from equity form to capital form after the development of the venture enterprise it invests in is relatively mature. Different from general industrial investment and strategic investment, venture capital does not gain industrial profits by operating products, nor does it hold the equity of the invested enterprise for a long time to cooperate with the parent company's product R&D and development strategy, but aims at obtaining capital appreciation income. The whole process of its capital movement is just like the description of capital circulation in Das Kapital: G-W … P … W'-G', from G to G', capital circulation is completed, and capital appreciation is realized in the process, that is, G'=G+ΔG (or G' >; G）。 Therefore, venture capital itself is capital operation, and its biggest feature is circular investment: investment-management-exit-reinvestment. Therefore, the exit mechanism is essential as an important part of venture capital. Only by establishing a smooth exit mechanism can the capital cycle be completed and the capital appreciation be realized. The exit mechanism not only provides continuous liquidity for venture capital, but also provides continuous development for venture capital.

in the United States, where the development of venture capital is the most mature, venture capital mostly exists in the form of venture capital, and the limited partnership system is popular, generally valid for seven to ten years. Before the validity period comes, all project investments must be withdrawn and the profits returned to the investors. If a fund has a good financial return, most of the original investors are willing to overweight the next fund, and new investors are willing to follow up, thus forming a virtuous circle and getting bigger and bigger. Therefore, VC is like the blood circulation system in the human body and must be circulated. If this virtuous circle is completed, the most important thing is to realize withdrawal, which is the key to connecting the preceding with the following.