Why is packaging 3D model flat when render?

Packaging 3D models often appear flat when rendered due to insufficient material texturing (e.g., missing specular/roughness maps) or inadequate lighting that fails to highlight depth and contours. Textures define how light interacts with the surface—like a glossy box reflecting more light than matte paper—so without them, the model loses its 3D shape. Lighting creates shadows that emphasize edges and folds; weak or uniform lighting makes these details disappear. To fix it, try adding basic texture maps (e.g., roughness for paper) or using soft directional lights to bring out the packaging’s contours.