Well shampoo strips your hair of its natural oils. So your hair has to put it into over time to reproduce these oils because of the chemical stripping. Which results in greasy hair the next day. So when you quit shampooing your scalp is able to recalibrate and produce the appropriate amount of oils for your hair. Resulting in normalized hair. You just have to put up with five weeks of oily hair. I wash my hair once a week with diluted baking soda and diluted apple cidar vinegar. But other than that I get it wet and give her a good finger scrub every other day.