How often should someone with afro american hair, like myself, use a clarifying shampoo?

I always heard once a month, but why?How often should someone with afro american hair, like myself, use a clarifying shampoo?
once a month is all I would recommend. It dries African American hair out really bad.How often should someone with afro american hair, like myself, use a clarifying shampoo?
i would suggest 1 every other week so it doesn't flatten your hair
1 a week