What you see on the box is not usually what you get because hair color on the box is applied to bleached hair:
Hollywood is a land of the perpetual blonde. However, blonde is not as easy to achieve as it may seen. Usually it takes a professional to do it the right way. Do not try to lighten your hair from a level 3 brown to a level 9 light blond with a box hair color. You can not "lift" or lighten more then 2 levels. You will have the most success with home coloring if you are just slightly changing your hair color. Like adding the same color as your existing color to add richness or going darker. When going 2-3 levels higher than your natural hair color, you must first destroy some of the natural pigment by bleaching or a less harsh word decolorizing, removing natural and artificial pigment in your hair. This should really be done by a professional colorist. Home hair color products and salon hair color products are truly different. During schooling, stylists become chemists. They are taught how to use these chemicals with caution and in the correct way. The FDA regulates drugstore hair color products and keeps their ingredients at such a low, SAFE level that they become almost ineffective. This isn't a case of name brands are better but the items are the same. The two product lines are totally different. Besides, professional colorists are more skilled and experienced.