Let's be real. What incentive is there for the McCaskey's to field a winning team? They're making money, they don't give a fuck about football, and they have zero pride (or their pride can't be hurt by losing).
You're asking McDonald's why they aren't trying to get Michelin stars. They don't have to. People will eat their crappy food forever. Bears' fans (like all of us) will live with crappy game play forever. If anything, losing teams have more rabid fan bases than winning teams (no bandwagoners, I guess).
I'm betting Nagy won't be fired this week. I'd love to be wrong.
Edit: Grammar and spelling. (FFS)