3d textured mapped images vs flat shaded images

The differnet between 3D objects that are texture mapped and those that are flat shaded/colored. So these two tanks look fairly similar. Image one is the texture mapped object and image two is the flat shaded image. The difference between the two is apparent in the colors. But looking at the images closely you can see that image one captures much more of the body of the tanks. I see this especially in the wheels. Where as image two clearly shows details of the wheels, It doesn't appear to have depth. more of the shade and coloring show the wheels. The same goes with many other parts of the tanks such as the bulk head.