Ah. I got the skinny now.
In 1998 Kiper said that Washington State Quarterback Ryan Leaf's "attitude" (which had rubbed teammates and coaches the wrong way in college) would be an asset in the NFL and give him a mental advantage over Peyton Manning. Kiper also said that Leaf had the better natural physical tools and would be a great quarterback, though he still rated Manning as the more polished and better overall prospect. Leaf was chosen second overall by the San Diego Chargers immediately after Manning. Leaf's career soon imploded, largely because of a confrontational attitude and poor practice habits that alienated teammates, coaches, and fans. He is now regarded as not only the worst bust in NFL draft history, but also possibly the biggest bust in all of professional sports.