It is rumored that for improving the crooked nose, one surgery is not enough. It is also said that even if the nose is straightened, it will be crooked again and need another surgery. It is not true.
It is not true that a crooked nose cannot be straightened with one surgery. On the contrary it should be. But there are some reasons that make the person needing another surgery. The main reason is asymmetry of nose at the same time as asymmetry of the face. For example a person who has hurt his nose when he was child and the intensity of trauma was so high that made the face grow crooked.
Crooked nose in a crooked face may have caused this imagination that the nose is not straight while the nose is straight but the face is still crooked and asymmetrical. If the face is symmetrical but the nose is crooked and the surgeon does not fix the crooked nose properly, it is also possible that the nose becomes crooked again after a while. But it is not something that happens inevitably. If the surgery is done accurately crooked, nose will be straightened and fixed with one surgery.
Please also remember that nose is not an object. Reshaping the nose is very different from reshaping wood and metal. Wood will not react to the carpenter’s art work, but nose (as a living organ) will react to the surgical operations and might undergo changes that are not completely under surgeon’s control. Therefore there is no guarantee about the result of rhinoplasty.