A musty smell, discoloration, or staining that returns after a past leak can be a reason to look closer. Warped baseboards, swollen cabinetry, peeling paint, soft drywall, or flooring that has changed shape can also point to moisture that has not been fully resolved.
These signs do not identify the cause by themselves. A stain can come from a past event, an active leak, condensation, or water moving from another area. The practical next step is to assess the source, the materials involved, and whether the affected area needs containment, drying, or removal.