Here's why:
* Color sets: The color needs time to fully set and penetrate the hair shaft. Washing too soon can wash away the color and leave it uneven.
* Cuticle closure: Hair coloring can open the cuticle, making hair more porous. Waiting allows the cuticle to close back up, preventing color fading and damage.
* Shampoo ingredients: Some shampoo ingredients can strip color, so waiting ensures the color is less likely to fade.
However, it's always best to follow the specific instructions provided by your stylist or the hair color product you used. They will be able to provide the most accurate advice for your particular situation.