When I was a kid, my dad ran a metal shop. Out back, he had heaps and heaps of scrap steel. Pieces of machines, broken tractors, metal shavings, odd cuts of steel plate. My dad did this because steel prices are volatile, and if he timed it right, he could clear his scrap inventory and realize large gains.
Steel is one of the basic building blocks of modern civilization. We use steel to build modern residential and commercial space. We use it to create factories. We use it to create car frames, both electric and ICE. We use it to create windmills, to create solar panels, to create roller coasters, air planes, cruise ships — nearly everything. Metal is so valuable to humanity that periods of history are named after which metal we were using at the time (Bronze age, Iron age, etc.)
When the price of steel rises and falls, it changes the intrinsic value and reproduction cost of assets. If the price of steel doubled tomorrow, automakers would raise their selling price.
The price of steel is essentially a composite of the cost of the inputs of steel: coal, iron, and the associated mining, transportation, and refining processes.