If it is generally thought that oil prices will be higher in the future, owners of oil reserves will tend to postpone costly investments in exploration and expansion of production capacity, and they may pump oil at below capacity. They would rather sell their oil and invest later, when prices are higher, so they restrain increases in supply.
如果人们总体上认为未来的石油价格会更高，那么油田的所有者就会推延在开发和扩大产能方面的巨额投资，而且还可能将石油产量压制在生产能力之下。他们宁愿在油价更高时才售油和投资，所以会遏制石油供应量的增长。这些预期成为可以自然实现的结果，油价上涨，投机的泡沫随之出现。