Not to absolve him of all the blame, but having probably the least talented roster in the league and a rookie starting QB has never resulted in many wins.

At that other site, some people suggested that he was not flexible, and particularly that he changed up blocking schemes to install his preferred system without having the right personnel, so the already mediocre OL regressed. You can try to scheme and "athlete" your way around a poor line, but you are really fucked if you have a terrible one.