Weird shading on 3D car models during styling typically stems from mismatched material settings, incorrect lighting, or poor UV mapping.
Materials with wrong metallic/roughness values (e.g., too high roughness for glossy paint) can look flat or overly shiny. Harsh, unbalanced lighting creates unrealistic hotspots or shadows. Poor UV mapping stretches textures, messing with how light interacts with the surface.
To fix it, align material properties with real car references (use 0.1–0.3 roughness for glossy paint) and switch to softer, natural lighting—this often resolves most issues quickly.