Because he thinks he is the only one that can coach this team.....Jerry has ruined the Cowboys and turned them into a bad circus. He reminds me of KISS in a way, after their heyday in the 70's they kept trying to catch onto the next in vogue music format...going from disco, to pop metal, ballads, even tried a grunge record...all to no avail...Jerry has tried he lackey buddy as coach, tried to save face when he hired an NFL guy in Gailey, then went with the guy he could control (Campo) when he wouldn't get anyone to take the job because he ran the salary cap into the ground, then he hires Parcells and as the team is beginning to take shape, he brings in the circus in TO, Tank, Pacman....then he hires another good ol boy that he can control and we have the current mess...total dysfuntion, no hit singles, no playoff wins, nothing buy disappointment and unfulfilled expectations....