When you say "does not exist", you mean that the short seller does not hold it. Generally speaking, "short selling" means borrowing an underlying asset to make an unprecedented move → selling at a high level → buying back when it falls → returning → earning the difference. Naked short selling does not need to borrow any basic assets in advance. Just click the "short selling" button on your trading software, and the transaction will be completed within one second, which is as convenient and quick as buying more. Only in this way can we really be short-term, repeat in one day, short on rallies, buy more on dips, and attack many times.
China lacks a perfect stock short selling mechanism. The United States can short, but it cannot do "naked short selling". It must first borrow the basic assets and pay a certain amount of guarantee capital. At present, only the foreign exchange market and futures market (including China) can do naked short selling, which can be said to be a real speculator's paradise.