Ideals of beauty are a constantly changing product of culture, religion, visual appeal, genetic response, marketing, and social mores. Historically and presently, those whose appearance is out of step with some perceived norm, which is usually defined by the majority or those in power, suffer discrimination. Those who have felt that their appearance (whether a result of age or genetic endowment) is unattractive or otherwise limits their options sometimes resort to extreme and potentially dangerous procedures to modify their appearance.
Of course, for many, "beauty is in the eye of the beholder," and familiarity breeds fondness, rather than contempt. Children who have good relationships with the parent of the opposite sex often seek out characteristics of that partner in future mates. Personality traits also affect how one is perceived by potential suitors. A "perfect" physiognomy can turn "ugly" if its possessor exhibits arrogance, immaturity, or lack of intelligence. Conversely, physically unattractive individuals with warm and outgoing ("radiant") personalities can appear "beautiful."
Perhaps one day we as a society can change our minds about the relevance of external appearance, rather than feeling the need to change our bodies. And maybe, the aged will echo the words of the French playwright Racine, and value their wrinkles as "the imprints of exploits," evidence of a life fully lived.