Waxing doesn't hurt too much- it can be a little painful if you have never tried it before. The best comparison would be ripping off a very sticky band-aid. It stings, but fades away quickly. The pro is that it will look nice when you're done; just avoid waxing for the first time before any events, like weddings or prom.
You didn't specify whether you were speaking of your upper lip, bikini line, or legs. Yes, waxing does hurt, just to varying degrees depending on the sensitivity of the area.
Waxing your upper lip can feel more painful than waxing eyebrows because it is not used to the heat of the wax and pulling of the hair from the root. However after waxing the area regularly the pain is similar to that of regular eyebrow waxing.
