Cards That Never Were: 1983 Fleer Tom Seaver

Are all baseball cards with errors valuable? I found an old fleer card not really worth anything but it has a defect clearly from the factory, I can't find a similar error

1976 Topps Tom Seaver

Tom Seaver Trading Cards: Values, Tracking & Hot Deals

Tom Seaver Trading Cards: Values, Tracking & Hot Deals

Page 2 : A pack of baseball memories

1970 Tom Seaver 300 Topps Baseball Card Sharp Corners No - Singapore

1981 Fleer

Cards That Never Were: Tom Terrific

Five Tom Seaver Baseball Cards Vintage MLB Card Lot - Denmark

Cards That Never Were: Tom Terrific

Collector Time Machine: 1983 – Jason Cards

19 Ways the 1983 Fleer Dan Norman Baseball Card Will Make You Happy – Wax Pack Gods