Regarding Minnesota, they went from 37th in total defense in 2017 to 59th in 2019 so you could argue they went from being good to average, and yet Fleck saw a poor trajectory and made the executive decision to change course.
I agree that Nebraska sucked defensively in 2017 (ranked 116th in total team defense), but they were in the top 35 in 2016 with Banker. In 2018 Nebraska was 88th in Total Defense and are currently 81st and still have 2 of their toughest opponents left on the schedule. Banker's results have been better than Chins and Banker was let go. I realize the talent and competition are always different depending on what year you are looking at, but at the end of the day, has Chinander met or exceeded expectations in Year 2, or has he struggled more than expected. I think most fans believe the latter, and its ultimately up to Frost if he believes Chin is the answer for the future. The reality is that Chin has NEVER led a stout defense as UCF had to score 50 points in most games to beat their toughest competition.