Final answer:
The liner in a protective coat should never be removed because it provides insulation, wicks away moisture, and preserves the shape of the coat.
Step-by-step explanation:
The liner should never be removed from a protective coat because it serves an important purpose in providing protection and enhancing the performance of the coat. The liner helps to insulate and keep the body warm by trapping a layer of air between the coat and the body. It also helps to wick away moisture, keeping the body dry and comfortable.
An example of this can be seen in winter jackets which often have a removable liner. The liner is typically made of a material like fleece or down, which provides additional insulation. Removing the liner would result in a loss of warmth and comfort.
In addition, the liner also helps to preserve the shape and structure of the coat. It provides stability and prevents the outer fabric from sagging or becoming misshapen. Removing the liner could compromise the overall durability and longevity of the coat.