Google "diffuse reflection" and "specular reflection" if you're interested to understand why. Things do not radiate uniformly, neither behave like mirrors (spe

Google "diffuse reflection" and "specular reflection" if you're interested to understand why. Things do not radiate uniformly, neither behave like mirrors (specular). The truth for most objects is somewhere in between. You can see it with a plastic object as well, when it is positioned so that the angle to the normal vector (a vector perpendicular to the surface) of the light source and to your eye are the same (as in, you would be able to see the light source if it were a mirror), you see much more light than when you are simply looking at it "from the side".