Why would a person want assets with liquidity?

Why is liquidity an important consideration for investors when selecting assets? Wouldn't it be more advantageous to hold onto assets that appreciate in value over time, regardless of their ease of conversion into cash? Wouldn't it be risky to have assets that can be easily bought and sold, as this could potentially lead to price volatility? Can you elaborate on the benefits of liquidity and why it is a crucial factor in asset allocation?