The team just never finished quite bad enough to ever draft truly elite young talent, the kind who can actually drive a team to the playoffs. Ending up with a group of good, but not star level talent just isn't enough.
Wings fans have also overestimated just how many of their prospects would reach their ceilings (few players ever truly do).
Yzerman is a decent GM, but not a miracle worker.
And the team has been stuck in a rough division with four teams consistently better than the bottom 4.