It comes down to the human resources capacity within the individual departments and agencies. They simply don't have the resources to do the processes in a timely manner.
I was at Canadian Forces Base Esquimalt out in Victoria just a few weeks ago. I was told by the admiral, the base commander, basically, that he has no other choice but to hire contract workers because he can't hire public service fast enough. They have a brand new building out there that needs to be maintained which are our members' jobs. He said he can't hire the public service to maintain that building. He has to hire contractors because of the hiring processes.