The reasons can be varied and can be multiple and include: color, engraving gone wrong, labeling done wrong, surface skuffs/dings, pin distances less then 1" from Pin to CG and pin distance greater then 5.5" from Pin to CG.
[F094] New NIB Roto Grip Clone Bowling Ball | 1st Quality 15lb
New NIB Roto Grip Duo Bowling Ball | 1st Quality (14lb/15lb/16lb)
Roto Grip Magic Gem Bowling Ball 1st Quality | 15 Pounds | 3.5-4" Pin | 3.91ozTW
New Roto Grip Gem Bowling Ball | 1st Quality
Roto Grip Gem Bowling Ball 1st Quality | 14.12 Pounds Mid Weight | 3-3.5" Pin