Describe the role of a primer in eyelash extension application.

A primer is essential in the eyelash extension application process because it properly cleanses and prepares the natural lashes for optimal adhesive bonding. When applied, a primer removes any residual oils, dirt, and makeup from the natural lashes, creating a clean surface that enhances the effectiveness of the adhesive used to attach the extensions. This preparation is crucial; it ensures that the extension adheres firmly to the natural lash, which helps prevent premature shedding and promotes longer-lasting extensions. A well-prepared lash will bond better with the adhesive, reducing the likelihood of lifting and ensuring the extensions remain in place for as long as possible.