To protect the surface from damage- Finishes such as varnish, paint, or sealant act as a protective layer that prevents moisture, heat, dust, and scratches from damaging the material—especially wood or metal. This helps the object last longer and maintain its strength.To improve appearance- Applying finishes also enhances the visual quality of an item. It brings out the natural beauty of wood grain or adds color and shine, making the product look more attractive and professional.