In 2015, he got completely beaten and bludgeoned with a labrum injury, partial abdominal tear and a lacerated kidney. During the offseason in 2016, he separated his AC joint snowboarding in Colorado. The snowboarding injury didn't affect the labrum but did further destabilize that entire region of his body. He has since spoke to the public that he had what he calls a "deep, deep, deep, deep, DEEP" code within himself to never cede to pain, and especially to not discuss it. At some point, Luck has some blame here and his trip to Holland was basically the beginning of the end of his career. Luck never fully opened up about his mental health during all of it and the organization probably just took Luck for his word.
Bottomline, had the organization paid better attention and been more in tune with Luck, we might still be seeing him on the gridiron.