In many papers in the field of spacecraft trajectory programming, the authors always convey to readers that the sequential convex optimization method is not a nonlinear optimization, but a convex optimization method that can efficiently solve general non-convex problems, like an omnipotent hammer. However, after several years of research, I believe that the above viewpoint is incorrect. The sequential convex optimization method is actually a nonlinear optimization method. Scholars in the field of nonlinear optimization have long proposed sequential linear programming, sequential quadratic programming, etc. There is no essential difference between sequential convex optimization and these methods.