Short positions allow traders to sell instruments without owning them by borrowing from the broker with the expectation that the price will decrease in the future and they will buy them back at a lower price. After the traders pay back their brokers, the difference is the profit generated by the trades. 

Here is how a typical short position works:

• Borrowing the asset: To initiate a short position, a trader borrows the asset they intend to sell short from a broker. This borrowed asset is typically stocks, but it can also include commodities, currencies, or other financial instruments
• Selling: The trader sells the borrowed asset on the open market. This step is executed in anticipation of a future decline in the asset's value
• Buying back at a lower price: After the asset's price drops, the trader buys it back at the reduced price, aiming to profit from the difference between the selling and buying prices
• Returning the borrowed asset: The trader returns the initially borrowed asset to the broker, completing the short-selling transaction

Short Position Example 

To better understand how short-selling works, let’s look at an example of a short position. For example, let’s assume that a trader believes that the stock of Company A, which is currently valued at $100 per share, will decline in the future. 

The trader borrows 10 shares of Company X from their broker and sells them on the market for $1,000. Subsequently, the stock price drops to $80 per share.

The trader then buys back the 10 shares for $800. The trader returns the 10 shares to the broker, making a $200 profit ($1,000 - $800).

As we can see, successful short-selling can deliver considerable returns over time. However, it is important to consider the implications of the position going against the trader, at which point, the potential losses are unlimited, as there is no upper price limit for a listed stock. 

Short-selling comes with a degree of risk and potential pitfalls that can lead to substantial losses. Traders need to be conscious of these factors in order to avoid losing their portfolios due to unaccounted risks.

Some major short-selling pitfalls to avoid include:

• Unlimited loss potential: Unlike long positions, where the maximum loss is the initial investment, short positions have unlimited loss potential. If the asset's value rises significantly, the trader may face substantial losses
• Timing challenges: Short selling requires precise timing. Predicting when an asset's value will decline is challenging, and mistimed short positions can lead to significant losses
• Borrowing costs: Brokers may charge fees for borrowing assets, adding to the overall cost of maintaining a short position

Short Squeeze

A phenomenon known as a "short squeeze" occurs when a heavily shorted asset experiences a rapid price increase. This happens when traders keep buying a shorted asset, which forces the investors holding short positions to buy back at higher prices - further driving up the price. 

The GameStop short squeeze of 2021 is a notable example of how such anomalies can affect the market and deal heavy losses to institutional investors.

• When a trader opens a short position, they sell an instrument at the current market price, with the expectation to buy it back later at a lower price. The trader profits from the difference and has to pay back the initial instruments to their broker
• Short-selling is a popular strategy to take advantage of declining security prices on the market 
• The strategy can be highly risky, as assets do not have a theoretical upside limit and could grow forever, leading to substantial, ballooning losses to the trader