It really depends. Some people end up looking asymmetric and their bodily ratio is broken. Some people really do have a gigantic nose and that ends up being fixed. Most people who get the job done will look less natural though, which isn't cool. People should be happy with themselves the way they are. It's not their breast size that defines them. Those who get a breast reduction because they have a ridiculous size and just can't handle it are different. Those who have a C cup and want a D cup should just look for other things to improve. It really depends on the overall image of the person: if it looks awkward afterwards, then it wasn't worth it.
I think that we all have an audience to play to. Nobody is considered universally attractive to everyone. We need to learn that there will be people who find you attractive even if you don't believe it yourself.
I have friends who had plastic surgeries and they look pretty now.. They were really stressed out about their looks so i think surgery improved their personality as well but i dont like a person who got surgeries on whole face that made her totally different person.