This question really lies at the core of how you describe a facelift. There are a myriad of facelift types, such as: smas-ectomy, smas plication, deep plane, etc..... They differ by how the superficial most muscle layer of the face, the "SMAS" is treated. Historically older facelifts started by separating the skin from its underlying muscle and tugging on the skin to lift. This left faces with a pulled unnatural skin look without much effect on the jowels and turkey neck. Most facelifts nowadays separate the skin from the smas, then somehow pull the smas up: in the smasectomy, some of this muscle and fibrous tissue is cut out then the gap is sewn together. In a smas plication, the muscle it just folded/bunched onto itself with sutures. The most advanced facelifts are those in the Deep Plane, whereby the skin is left connected to the smas, and the surgeon gets into the tissue layer underneath the smas, using the smas muscle to do the lifting, taking tension off the skin. In the extended deep plane approach the ligaments that are teathering the undersurface of the smas are also released so the smas muscle and skin dont need to be pulled at all, just resuspended into their natural position vertically, leading to a longer lasting, more robust tighter jawline and neck. Recovery and scarring after a deep plane lift also proceeds quicker as the skin is left connected to its blood supply and incisions heal without any tension on them. Hope you find this long winded answer useful and not too confusing!