Liquidity means the ability to buy or sell a particular asset quickly without significantly affecting its price. In highly liquid markets, like the BTC/USDT pair, there are always buyers and sellers, making order execution fast and easy. In low liquidity markets, you may face delays and price slippage. Liquidity also affects the spread between bid and ask prices. Therefore, traders should be careful to choose pairs and platforms that have sufficient liquidity to ensure efficient trade execution and reduce hidden costs resulting from price fluctuations.