Regarding nasal reconstruction vs. a rhinoplasty?

This may be a dumb question. If a nose can be rebuilt after having cancer where much of the tissue is removed, and still look decent, why is it seemingly impossible to make A nose that has had multiple revisions look "normal"? What is the difference between rebuilding a totally deformed cancer stricken nose as compared to rebuilding a nose that has been botched by prior surgeons? Thanks for input.