Big R, Just a snippet from that article:
"The different players have different reasons for storing oil, whether onshore or offshore.

National oil companies are hoping to reverse the price slide by holding oil off the market. Iran alone is reportedly using as many as 15 tankers to store crude oil in hopes that higher prices will prop up its economy, which is dependent on oil exports.

Private trading companies like Vitol and Phibro are storing oil in expectation of higher prices. They are taking their cues from markets where traders buy and sell contracts for future delivery of oil, which are signaling higher prices down the road.

Adam Sieminski, chief energy economist at Deutsche Bank, noted that a trading company could buy oil at the spot price of nearly $40 a barrel, store it and sell a contract to deliver it in a year for about $60. “You pay between $6 and $10 a barrel to store it, and you can make $10 a barrel,” he said. “That’s why Cushing is filling up rapidly and people are leasing tankers.”

Not that that art. is the final word, but I ref it as it is as good and clear
as I've found on the topic, lately.

If "you" had millions of bbls in storage, "you" would be working the chain of
rumor, innuendo and every other network aspect to get that commodities
price heading north again, imo. "You" being the gang(s) that control the
prices among other things.
BR,mD