What cosmetic result is often not achieved immediately after applying a product that successfully kills live mold spores?

Removal of the visible stain or discoloration left behind by the dead mold.

While many quality mold control agents are highly effective at their primary job—eradicating the live fungal organism—their success is not always immediately apparent in terms of aesthetics. When a product successfully penetrates and kills the spores via crushing or other mechanisms, the biological organism ceases to be active, but the physical byproduct of its prior existence often remains. This byproduct manifests as residual discoloration or staining on the surface material, particularly on painted surfaces or porous substrates. Therefore, even after the underlying biological problem is resolved by the treatment, homeowners may still need to undertake separate steps, such as cleaning or repainting, to address the cosmetic evidence left by the mold growth.