IPL laser hair works on dark hair that is in the right cycle of growth (anagen hair). This cycle is exactly 3 weeks after plucking/waxing under the skin and 4 weeks just poking through the skin.
The only reason why a hair will come through sooner is it had not been successfully pulled by the root.
On the face only seems quicker because the follicles are more shallow.

The only reason IPL laser hair will not work completely, is the hair was not dark enough to begin with or if it is dark it was not in the right cycle, older 5 weekly hairs are dry follicles and not the right window of opportunity!
This is easy fixed, hair removal is my thing and i know about hair cycles and how to get the hair into the correct cycle!
Medical grade IPL laser  will also work a lot better than beauty grade machines. If the skin is darker however, we will turn down the joules and the result is therefore compromised.  Often though some people with darker skin have a better contrast and so the results may be better! Most people are still happy with this lessened result.
There are ways if still killing the remaining hair, through waxing the remaining hair and loofah routine over the following year post last IPL laser hair treatment. Electrolysis is great and permanent for any light hairs you want to kill forever. For some hair which is which is light or hair that is darker but has not worked because skin is too dark or hair that is dark but has a tinge of auburn when held to the light!

Call Bare Bella on 0425765971 to make a consult or book online here!