Theoretically, the futures price is formed by the spot price plus the cost of holding positions. The cost of holding positions is usually fixed, so in theory, the futures price fluctuates with the spot price. However, according to the experience of mature markets in Europe and America, because the vast majority of participants in foreign markets are in the spot background, mature markets have actually formed a situation in which futures guide spot. Everyone is doing the spot, and the expectation of future prices is more accurate and rational. Therefore, when people expect the future price to rise, some people with strong financial strength may start hoarding goods in the spot, which will lead to the spot price rising with futures. This is the same as the essence of hedging, and futures guide the spot. Another reason is that people expect prices to rise, and futures funds are more flexible and responsive. Before the spot price rises, it creates the illusion that the spot follows the futures.

In China, the same is true of some varieties with large delivery volume and many spot traders, such as cotton futures, which simply become the spot market.