Because it will give you the lighting you want (the right lighting) you can give a photo certain emotions by changing the light. Also if you don't pay attention to it, it may affect the picture you are taking negatively such as the color the clearness, etc.
The answer is repousse. It is a method having to hammer
something from the reverse side to produce relief such as to imprint a design
using the other side rather than using the front side of the metal in which it
is described above.
