Why is the Monalisa painting so famous?

On this occasion I tried to paint a so famous painting that is Monalisa, As I usually painted using the HB, 2B, 5B and 8B pencils. My paper is using A4-size Cancon papers, Following is the step by step of the representation

Step 1

Step 2

Step 3

Last Step

Thank you so much for having to see my picture