Which statement is NOT true about acid perms?

Acid perms are specifically designed for fragile or damaged hair due to their gentler formula, allowing for a more controlled curl formation that is less damaging compared to alkaline perms. The statement that acid perms are better for use on resistant hair is not accurate because resistant hair typically requires the stronger formulation found in alkaline perms to effectively penetrate and alter the hair structure. Acid perms process slower, which contributes to creating soft and natural curls, making them suitable for various hair types, particularly those that are fine or damaged.

Thus, recognizing that acid perms are not ideal for resistant hair clarifies their intended use and highlights why they are preferred for other conditions.