I found the same polished cover labelled good and scratched in our FR10 trial folder. Different lighting. Can we settle the physical sample's condition before someone tunes a threshold to these labels?
Please do, because a threshold can't referee an argument nobody has finished; get quality to inspect the identified cover, then use the two images to investigate why its appearance changed.
Keep some confirmed damaged covers in the next comparison too. Making this good cover look good is only half the job. You also need to know that real damage remains visible under the chosen conditions.