Ombre hair color Mistakes and Correct

Ombre hair color is as long as I see it, just grow the hair color left 2-3 months show the demarcation.
Myself I don't care about it, but its fashion, my daughter, asked me to do her hair for Ombre.
Asian girl has dark hair when thy do Ombre too much contrast 
Caucasian girl has light hair color more branding contrast color