The dude has burned through coaches, HoF coaches, until he got his puppet in Jason Garret. I wouldn't even hire Jason Garret to be the waterboy of any team, and yet he's the HC of the worlds highest valued sports team.
Jerry Jones may have turned the 'Boys into a mega-money franchise but the dude is such a foolishly proud individual that he won't just leave the experts to do their thing. He needs to hire a GM (not his golden spoon fed son) that will handle the football operations and allow that GM to hire their own coach. For all the money Jerry's paid his players it won't do him any good so long as he has an underqualified turd of a coach leading them.