This is education, not advice
The information here is written for the general reader and does not replace a personal medical consultation. It cannot tell you whether your problem is fat, skin or separated muscle, which is the question that decides between these two operations.
No outcome is guaranteed
No treatment can be guaranteed. How much either operation changes the contour, how the tissues settle, and how the scars mature vary between individuals, and the result of either is judged honestly only after six to twelve months.
Scars are permanent
Fat removal leaves small access scars and an abdominoplasty leaves a long transverse scar across the lower abdomen. Both are permanent. They mature and soften over a year or more, and no surgeon can promise that either will be invisible.
Revision carries added risk
A second operation on an abdomen that has already been operated on is a harder operation on tissue that has already been changed. Revision does not remove the risks of the first operation; it adds to them, which is why this site discusses it before the first operation rather than after.