Investors must be aware of the lock-in period, which restricts them from redeeming their units immediately after making new investments. This time frame is predetermined and varies based on the type of investment. It is an important concept to understand in finance, as it affects the liquidity and flexibility of an investment. The lock-in period serves as a safeguard for the investment, allowing it to grow without any interference. It is a crucial aspect to consider when making investment decisions.