Polygon 3D models' underlying structure is often hidden because final renders or real-time displays use textures, lighting, and shading to cover the polygonal mesh.
The raw polygon grid (made of vertices and edges) is masked by surface details to create realistic or stylized visuals—users interact with the finished appearance, not the wireframe. For example, games overlay textures on polygons to make characters look smooth, while animations use compositing to hide the mesh with color and light.
To see the polygon structure, most 3D software (like Blender) has a wireframe mode—this lets you check the mesh without altering the final look.