Bears tried to trade for Mike Tomlin
The McCaskey family is always trying to prove that they're the smartest people in the business. They're always shopping at Dollar Tree for value instead of buying a guaranteed quality product (all Chicago teams do). They always Bears it up. Even when they get an uncut diamond (high pick quarterback) they refuse to do what's necessary to get the most out of it. They're the type to have an exotic sports car and take it to a random mechanic in the neighborhood instead of to a place qualified to work on such a vehicle.
As long as that family owns them it'll be this way. They meddle. They think that football knowledge is genetic and they won't let the actual football people do it. Grandpa knew football so they do too.
They'll have the occasional good season and then kill it after they look at the expense sheets. They know that the meathead fans will show up anyway.