With proper application, care, and touch-ups every two weeks, Xtreme Lashes can last indefinitely. Without regular touch-ups, a full set of lashes can last up to two months. That's because the life cycle of a natural lash is typically two to three months, during which time it grows, remains "at rest," and then falls out. Once it falls out, it is replaced by the growth of a new lash. At any given moment, your lashes are at different stages in the life cycle, which is why touch-ups should be performed every two weeks — to replace the lashes that have naturally fallen out.