[hempick]

I just notice that it was his first card on a major brand, but...he was drafted in 1984. Why didn't he have a card before 1988?

Nearly every other player (Jordan, Barkley, Malone, etc) had their first card in the 86-87 Fleer set, but not Stockton?

[odditycards]

You have to look at his stats. By all means, he was not a great superstar player from the get-go for his position. The 86,87,88,89 sets were very limited on the number of players that were included (as compared to today.
He really didn't have his breakout year until 1988, when his yearly assists total and points scored DOUBLED from previous three seasons.
Star did have a few earlier cards of him, and Panini picked him up in their first NBA exclusive set of 1988-89 as well. Only 1 or 2 local Utah SGA sets have him earlier that 1988 for "RC card"

[hempick]

Ah, yes, I see that now.

[altz11]

Odditycards mentioned it but John Stockton's first card which would be his "true" rookie card would have been in the 84-85 star set.
There are a ton of players whose rookie card isn't necessarily their rookie season.