If you want to give him a pass for unexpected under performance, that starts to ring hollow in light of such a thorough record of failure. The fact that everything he touches turns to garbage starts to reflect on him after a while. Also, I firmly believe that under performance was not his biggest problem. The team was very poorly constructed. If the staff had performed up to career standards, they still would have been a bad, noncompetitive staff.
Where I really disagree with you is the pass you give Ben as he sat back in 2012, 2014 and 2015 as his moves and experiments were obviously crashing and burning. He had a complete inability to pivot when his moves were going bad. He always seemed to behind the curve. He stubbornly held onto his belief that Bard could be a starter when the guy's career was disintegrating before our eyes. He let the 2014 team flounder as the lineup was in desperate need of help. He kept too many rookies in the lineup for too long as they were imploding. What happened to Bradley in 2014 went beyond letting him get by some rookie bumps in the road. It got to the point where he was useless to the team and his confidence was getting shattered. Even Remy commented that Bradley should have been sent to AAA long before he was. Ben had a pattern of holding onto things for too long and reacting only after it was too late. Bradley's career was significantly derailed by Ben's stubbornness in 2014. The Hanley experiment was just the latest in Ben stubbornly clinging to failure. Even as his replacement was being courted, Ben was still stubbornly stating that Hanley would not be moved fro the OF. While the GM can't control the performance of the players, his job doesn't end after building the opening day roster. He is the General Manager. Ben couldn't manage as things went wrong until the flaws became team fatalities. That was his biggest shortcoming. His inaction went well beyond wise patience to foolish stubbornness.