Because his team made the playoffs every year in dominating fashion, making it nearly impossible for other teams to make the playoffs! Ask Orioles fans.. they didn't make the postseason for 15 years during Jeter's career! And we would've made the postseason in 1998 had there been a 2nd wild card, and 2000 if we had more pitching depth. Don't rub it in!
Plus, it wasn't just Jeter, it also was Pettite, Posada, Williams, and Rivera as well, the core. Of course, late in Jeter's career, his team is looking like it'll miss the postseason in back to back years, barring a collapse of the Tigers, Mariners and A's(yes, the A's.. the A's are 14-16 in their last 30.) We all know the O's are going to win the AL East..