What is the primary function of a base coat in nail care?

The primary function of a base coat in nail care is to protect the natural nail from staining. When applying colored nail polish, particularly darker shades, there's a risk that pigments can penetrate and discolor the nail plate. A base coat acts as a barrier, preventing these pigments from staining the natural nail, thus preserving its health and appearance.

While a base coat can also contribute to other aspects of a manicure, such as improving adherence of the polish (which can indirectly help with durability), its main role is to safeguard the nail from potential staining caused by the colored nail polish applied over it. This protective function is particularly important for maintaining the overall integrity of the nail and preventing discoloration, which can be a concern for many individuals who frequently use nail polish.