Medically speaking, if you had hair on your upper lip, and it stopped growing after 5 years, it was not the waxing, but something else, like discontinuing use of a drug that you were having an interaction with, or some hormonal imbalance that was corrected.
Although one might get enough scar tissue in the eyebrows or legs to cause permanent removal in those thin skinned areas, the lips doesn't work the same way.
Many people also get permanent hair removal on their legs without doing anything simply because their circulation becomes less than it once was as one ages.
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Setting a goal is not the main thing. It is deciding how you will go about achieving it and staying with that plan. --- Tom Landry