I have a model that I sculpted and retopologised in another application, and then imported the retopologised mesh into Blender with a normal map.
The mesh is around 9200 verts, and I have smooth shading turned on.
While the surface is not perfect, it seems more than smooth enough that this artifact should not be happening.
The object has a normal map applied (baked from the high quality sculpt), but I can turn that off an get the same thing:
Here is a shot of the wireframe:
Is this abnormal like I think it is? What might be causing it? I have checked the mesh for everything I can think of.