a zero-sum game means that someone loses and someone gains. And the compensation is equal to the earned value, such as gambling and futures.

Stock is a virtual economy. When the stock goes up, almost everyone makes money, and when the stock goes down, almost everyone loses money.

For example, if you have an antique, some experts say it is worth 1, yuan. After a while, some people say it is worth 1 million yuan. Your wealth (virtual) has increased, but no one has lost money. After a while, some people say that it can only be worth 5 thousand, and your wealth (virtual) has decreased, but no one has made money.

of course, in short-term trading, the money lost by those who buy high and sell low is earned by those who buy low and sell high.