Here's why:
* Purple shampoo is designed to neutralize brassiness and yellow tones in blonde or lightened hair. It uses violet pigments to counteract the yellow tones that can make blonde hair look brassy or dull.
* It's formulated to deposit a temporary color. The purple pigments in the shampoo are designed to deposit a temporary color that washes out over time.
* The amount of purple pigment is minimal. The shampoo contains a very small amount of purple pigment, enough to counteract yellow tones but not enough to dye your hair lavender.
However, it's possible to see a slight purple tint if:
* You use it too often. Overuse can lead to a buildup of purple pigment, resulting in a temporary purple cast.
* You leave it in for too long. Leaving it in for longer than recommended can also lead to a purple tint.
To avoid a purple tint:
* Follow the instructions on the bottle.
* Use it sparingly. Once or twice a week should be enough to maintain your blonde color.
* Rinse your hair thoroughly. Make sure all the shampoo is rinsed out to prevent any residue.
If you're looking for a lavender hair color, you'll need to use a permanent hair dye.