There is not an easy answer. Opinions vary.
Traditionally patients were asked to massage the breasts after augmentation in order to stretch the pocket the implant lies in and thereby reduce the risk of the formation of a tight capsule deforming the shape. It might have helped.
Nowadays the surgical pockets are made to exact size and capsules, although still a problem, are less common. The usual advice is now to support the breasts in the correct position with a sports bra or medical equivalent for weeks or months.
Massage has never had a place in other types of breast surgery such as breast reduction, breast lift or mastopexy or breast reconstruction.
Again massaging scars has been almost universal as a means of helping them mature. There was nothing else to do.
Scar management at The Cadogan Clinic is now important with several levels of treatment. Sometimes massage is part of this. This applies to all scars and all types of breast surgery.