The price of agricultural commodities fluctuates, foreign exchange rates change from minute to minute, interest rates and equity indexes rise and fall.
Nothing stays the same.
And that's why futures are so useful and so essential to business operations all over the world. Supply Supply is defined as the quantity of a product that sellers are willing to provide to the market at a given price. When prices are high, sellers are willing to provide larger amounts of their products to the market. It's human nature. When prices are low, sellers are willing to provide smaller amounts to the market.