Why Do Some Breast Augmentation Results Appear Saggy?

The issue of sagginess has two components.
The first is related to the position of the implant on the chest wall. If the implant is placed low on the chest wall, even if it is in harmony with the skin envelope and nipple position, it will appear to hang too low, or sag.
The second has to do with the position of the nipple relative to the breast mass. If the nipple-areola complex is too low relative to the implant, the nipple appears to be pointing south.
In both cases the situation can be improved by performing a lift in combination with the breast augmentation. In my office, I stand the patient in front of the mirror and let her guide me as to where on the chest wall she wants the implant. Once I know what her ideal implant position is, then I decide whether a lift will help her.
For a link on the importance of implant position, see the link below.

The appearance of the breast after augmentation is related to the preoperative look. Therefore, augmentation of a sagging breast leads to a fuller, but still sagging breast.

Some patients are fine with this. They can do their own lift with a great bra, and avoid the scars and expense of a surgical breast lift.

Secondly, placing implants that are too large will create sagging over time. This is especially true of saline implants, which are about 20% heavier than silicone gel devices.

Thank you for your question. The final breast augmentation result depends on the amount of sagginess, or ptosis, present in the breasts pre-operatively, the surgeon's placement of the implants, and other factors. If the breasts have too great of sag (ptosis) pre-operatively, it may be better to undergo an aug/pexy, which both places implants and lifts the breasts through a mastopexy.