Mel Kiper predicted Trent Dilfer would be an elite quarterback, but he ended up being a disappointment.
Kiper ranked Lamar Jackson's accuracy as a concern, but Jackson has become one of the best quarterbacks in the league.
Kiper had JaMarcus Russell ranked as one of the top quarterbacks, but he turned out to be a huge bust.
Kiper predicted Blaine Gabbert would be a top-five quarterback, but he didn't live up to expectations.
Kiper ranked Ryan Leaf as a better quarterback than Peyton Manning, but Leaf had a disastrous NFL career.