Re-touching is more an art than a technical application. The issue most have with re-touching is leaving the client looking like a plastic doll. Way too smooth and unnatural. Re-touching only purpose is to solve the problems the camera brings to light. Most people interact with others 2-3 feet away. This distance makes it hard for the eye to pick up imperfections. Also, natural movements tend to blend those same imperfections making them less conspicuous.
The problem with photography is it is a still image only inches away from your face. It will show every imperfection and because it doesn’t move, the eye has time to see everything.
My retouching gives a finished look about what most would see standing a few feet away. You still look like the photo used online or on your business card.