Bennett, who was originally contracted until 2015, became a free agent following recent ownership changes at the Club.
The veteran coach has made this decision based on a number of reasons.
“First and foremost, I am not comfortable with the performance of the team over the three years and I take full responsibility for that,” Bennett explained.
“While we have been faced with many challenges, the Club is heading in the right direction and I have confidence in the structures now in place.
“I believe it will take a number of years to reach an acceptable position and that is what I am unable to commit to. A longer term coach is crucial for future success.”
The Club will commence the process for Bennett’s replacement.