You can't privately dump. Well, you can try.
Since you're selling at a loss on the open market, others with capital will see an unexpected price and wonder if you have developed a unique efficiency. After some basic research, some will guess at what you're trying to do.
They then have some great options. Invest in competitors or substitutes for the coming reduced supply. Or, stockpile the goods you sell, buying cheaply from you and even undercutting you in the future. Or, develop ways to reduce fixed costs. Build "fast spin up" sites with on-call labor so you can quickly return to market.
The dumping strategy works pretty well in a game with only two players. It does not work against the entire global system of capital and investment.