There is always a thought in the NFL that some owners get in the way of their own selves when it comes to hiring a coach. Typically, a team will hire one type of coach, and because that style does not work, they will hire the exact opposite type of person to be their next coach.
You can look no further than the Chicago Bears for this. The run has been pretty strong since Lovie Smith. Smith was obviously the defensive mind and an old-school coach. Once ownership decided it was time to spice things back up, they did not want a similar coach to Lovie Smith.
It may not be the exact opposite, but there are not too many similarities between Marc Trestman and Lovie Smith. Trestman was the new school offensive coach and way off of the wall idea from the same old that Smith seemed to instill from his long tenure.
When the Trestman plan fell on its face, the ownership immediately wanted to go right back to the old-school defensive mind. They could not hire Lovie Smith again, John Fox brought a similar mentality and background. He was also strongly different than Marc Trestman.
So, when Fox got stale, it was back to the new, young, and offensive. Matt Nagy is much more comparable to Marc Trestman in the same way that Smith and Fox have more in common than the former two.
It is obvious that since about 2012 the Chicago Bears have been flipping back and forth about what they believe their head coach should be. It could be argued that these issues have hurt the team building and backbone of the team, which has given these head coaches a tough circumstance to begin from.
Trestman had to win over Smith players. Fox had to build back the defense, and once the defense was built, Nagy had to quickly build back the offense. These coaches all failed, but arguably all were put in bad spots based on the previous coaching regime having different philosophies.
If this trend continues the Chicago Bears are bound to hire a defensive-minded coach. This coach will inherit an aging defense, and just as the offense starts to develop around Justin Fields, it will be hard to keep the defense intact.