Straight from Clevite 77's website as an example of a good bearing doing it's job:



Appearance: Wear patter covering approximately 2/3 of the bearing surface. Wear should diminish near the part line ends of the bearing surface. Pattern may be intermittent in both axial and circumferential directions on bimetal aluminum depending on geometry of mating surfaces.


Their Example of a scored bearing:



Appearance: Bearing surface deeply scratched and torn.
Causes: Excessive foreign particle contamination. Poor crankshaft surface finish. Insufficient lubrication.