Retouching
Good retouching should look natural, you shouldn't hear "nice retouching" from people, if it's that noticeable then it's not good work. Unfortunately 'over-retouching' is quite common as well as obvious and unsightly.
Look for retouching that retains skin texture while keeping shading and highlights natural. Avoid work from those who create 'glow in the dark' eyes, porcelain skin or any other image degradations. It's imperative you look your absolute best while still looking like yourself.
Below are some examples of good retouching.
Move your cursor over the sample images to view the "before" version.