What is the Hardest Part of the Nose to "Fix" when Doing a Rhinoplasty ?

If the surgeon is experienced and know what they are doing, none of it should be hard.  I can tell you the mistakes that I see most commonly in other surgeons' noses.  They are usually errors of under-reduction, which is good because the revision is simpler.  Often the bridge is not reduced enough or the bones not completely broken the way they should be.  Also some surgeons fail to shorten the nose adequately.  Now, not all my noses are perfect, and no surgeons' are.

Although each person has a unique nose and different desires for their appearance, the most difficult part of rhinoplasty for me is a patient who wants their nose to look like someone else's nose - maybe a particular celebrity or a friend's nose.  The best result will always come from understanding your own goals and expectations respective of your own facial features and balance.  Open communication with your plastic surgeon and looking at before and after pictures should help you develop a good understanding of what can be accomplished by your doctor.  Surgically speaking,  it can be very difficult to correct a rhinoplasty that has  a poor result; damage to cartilage or having removed too much of the tip is challenging for most surgeons to be able to repair. 

There is no one single part of the nose that is more difficult to fix than another.  Good rhinoplasty results require experience and good technique.

By far the hardest thing to fix is a rhinoplasty with poor results.  "Re-do" rhinoplasty surgery is by far the hardest.