People I know who have had it never seem happy, at least in the longer term. It never seems what they expected; or 'quite right'; so there can be a cycle of getting it fixed, or periodically redone.
A risk is hating how you look even more. Jocelyn Wildenstein likely feels that way... [x-ref the Frostrup article linked below).
There is as a UK TV comedian who lived on the neighbouring street to me, Leslie Ash. Born naturally good looking she must have felt the urge to 'improve things' and had lip implants. During surgery she got MRSA which nearly killed her. She looked like a freak, her career ended and a year or two later she had the op reversed. She seems to have vanished off the media radar completely these days. To some extent it must have wrecked her life.
Mariella Frostrup is another example, who happens to live on the same street as Leslie Ash. Take it from her...
http://www.theguardian.com/lifeandstyle ... urgery-old
p.s. I think a point made above is likely true, 'Look inside yourself, rather than into the mirror'.