Many investment assets, such as typical stocks and bonds, sit somewhere in between. They can be converted to liquid assets quickly, but not immediately.
Liquid assets are vital for financial security. You need them to pay for everyday expenses and short-term goals as well as emergencies and other unplanned expenses.
For long-term financial goals, it is necessary to put significant money into these assets, but healthy personal finance also requires liquid assets on-hand.
Make sure you always have enough liquid assets on hand to cover upcoming expenses as well as emergencies, and give the rest of your money time to grow.