They drastically increased production after covid, and then with inflation and the economy slowing down, demand crashed, meaning they had a fuckton of NAND and nobody to sell it to. They needed to get rid of it so they sold it all at a steep discount below the break even mark, losing billions of dollars in the process (I don't think any NAND manufacturer had a profitable 2023?). Now, they're cutting back production to profitable levels that actually meet demand, so prices will increase and return to normal.