Here is the core reason (s) and why he failed as a Green Bay Packer Top Draft Pick and a lot of that is certainly personality and (medically) mentally related:
http://archive.jsonline.com/sports/p...00153021.html/
PACKERS|OLD SCHOOL PACKERS
Feb. 28, 1993: Tony Mandarich’s decline is rooted within him
By: Bob McGinn, Milwaukee Journal ... Feb. 28,1993
"...whatever advancements Mandarich had made began to dissipate in the ’92 off-season. His travels and big-game hunting expeditions left less time for the weight room in Green Bay and reduced his aerobic activity. Then, on an Alaskan vacation in June, he supposedly drank tainted water and was in even worst condition for the start of training camp.
Over the next six traumatic months, he would suffer a severe concussion, learn he had a thyroid condition, make his final public media appearance in September trying to answer a damaging Sports Illustrated story, bow out near midseason as host of his own TV show, visit doctors across the country and be diagnosed as having post-concussion syndrome, list his home for sale outside Pulaski, Wis., defy coach Mike Holmgren’s request that he trains in Green Bay, and grieve for his older brother, John, who died of cancer Feb. 8.
When Mandarich attended the wedding of teammate Shawn Patterson in Green Bay last Saturday, two people who were there said they detected tears in Mandarich’s eyes on two separate occasions.
“Obviously, the combination of a concussion and everything else brought on some depression,” said Domenic Gentile, who retired Feb. 1 after 32 years as Packers’ trainer. ..."