Any surgery, no matter how minor, has the potential to be life-threatening through infection, reactions to anesthesia, or other complications. While most surgeries go off as planned, I personally can't understand why someone would take that risk for something they don't need. In addition, barring a serious injury or birth defect as mentioned before, if someone is unhappy enough with their body to get cosmetic surgery in the first place then the surgery is not going to make them happy with it. If they like the result, they'll most likely find another "flaw" that needs to be "fixed" and use the same fast fix they used to "fix" the last one. It seems to me that in most cases it's the attitude that needs to change, not the appearance.