I notice that in baseball there are only like 300 cards per series and there are over a 1000 players. Does every player make it order medicine online on a card and why does series 2 usually come out much later than series 1

I recently found what is left of my small baseball card collection. Three of these cards may be of some value. I have a Ken Griffey Jr. rookie card as well as Tom Glavine and John Smoltz buy prescription drugs on line in their rookie seasons.