Silhouette Soft Lift and what happens when it wears off?

I understand results from a Silhouette Soft Lift can last up to 2 years. After that, is it that the threads dissolve & the skin goes back to its original droopiness? or is it from natural aging & is it new sagging? This make sense? Is it like when someone gets Botox & the skin returns to its original state when the Botox wears off? It's not a new wrinkle, just going back to the original wrinkle. With SS, is it sagging back to its original sag or is the sagging new sagging due to aging? Thanks