I had a rhinoplasty done around 15 years back and I would certainly do it again if I could go back. My nose had been broken from bullying and I hated seeing it every time I saw my own reflection.

After I had it done I experienced a boost in my self-confidence, but that didn't last forever. Eventually I just found some other part of my appearance to obsess over.

I think why some celebrities do it is because they - more than anyone else - are constantly reminded of how they can look at their best. Even the male celebrities have makeup teams fix them up for interviews, photo shoots, etc and are expected to maintain a certain physique. Whenever people see them them, they would be expecting to see the look that the celebrity is known for. I'd expect that would make them hyper-critical about how their appearance, and prone to going to extreme lengths to achieve or hold onto that look.