Crude oil futures and energy ETFs like XLE may diverge from each other due to a variety of factors such as changes in supply and demand, geopolitical events, and overall market conditions. Additionally, crude oil futures are a direct investment in the commodity itself, while an ETF like XLE is a collection of stocks of companies in the energy sector, so the performance of the ETF may be influenced by factors such as the financial health and management of the companies it holds, in addition to factors affecting the price of oil.