Angelina Jolie's natural hair color is dark blonde. Why did she dye to dark brown for so many years?

Angelina Jolie's natural hair color is dark blonde. Her mother dye her hair when she was small. 

She explained, "My natural color is dark blonde. But when I was 4 or 5, my mother dyed my hair dark brown, and she decided to keep it that way. And I stuck with that".

Jolie claims her late mother, Marcheline Bertrand didn't like the light color on her, so she turned to dye.