According to the FDA, laser hair removal should be referred to as laser hair reduction because it doesn't always remove unwanted hair, but it can reduce or stunt hair growth. The lasers target the root of the hair to slow growth and may not be able to pinpoint light hair.
Laser hair removal procedures typically work better on coarser, dark hair and may not work as well or at all on fine, blond hair. Although the treatment may stop the growth of the targeted hair follicles, the body constantly creates new hair follicles. Therefore, new hair can still grow after the treatments are complete.