What is A bet that a stock will fail?

A bet that a stock will fail is commonly referred to as "short selling." In this strategy, an investor borrows shares of the stock and sells them at the current market price, hoping to buy them back later at a lower price after the stock declines. If the stock does fall, the investor can repurchase the shares at the reduced price, return them to the lender, and pocket the difference. However, if the stock price rises instead, the investor faces potentially unlimited losses.