The general opinion is that laser hair removal is considered as a “permanent hair reduction”. Generally, this means that you shouldn’t expect laser to remove every single hair from an area. Most will also need touch-up treatments 1-2 times a year after the initial set of treatments for any new growth your body develops with age.
It has also been observed that some people seem to be non-responders – this is not confirmed and reasons are not known as not enough research has been done in this area. Keep in mind that it’s also difficult to judge whether someone’s lack of results is due to the person’s potential underlying medical condition that causes continuous growth and makes it seem like laser isn’t working, whether the treatment wasn’t performed properly. Basically, you can’t determine this for yourself unless you try it for yourself.
A set of at least 6-8 treatments at specified intervals are generally necessary to achieve substantial hair removal with laser. Factors that determine the length of treatment include the particular area to be treated, the texture of hair, frequency of treatments, history of temporary measures to remove hair (waxing, tweezing, shaving, and depilatories, etc.) etc