This is very likely correct. I think they looked at the finances and the changes to the FFP rules and they decided that their main objective last summer was to balance the books (ie, players would have to be sold before any other were bought) and assumed we'd be able to muddle through this season before undertaking a major rebuild this summer.
Unfortunately they miscalculated. The squad had already started to go stale and the relationship between Rodgers and the players was in decline. Rodgers wasn't wrong when he said after the Forest FA cup humiliation that we badly needed a refresh, but it was foolish of him to say so in public. This meant that when the club decided to postpone the refresh until the following summer, Rodgers was forced to continue working with players he'd publicly thrown under a bus. This could not have been good for morale or motivation. Then Rodgers made the situation even worse by refusing to play his best centre half and goalkeeper, and sticking rigidly to the same tactics when it was obvious to everybody that it wasn't working. The team's confidence collapsed and Rodgers did not have the man management skills to turn it around.
This summer will be the most important close season in our history. We have 12-15 players to recruit and we don't currently know who the manager will be. All I know is that I'm glad it's not Rodgers - and I'm equally glad that Congerton will have nothing to do with our recruitment this summer.