The Pittsburgh Steelers are not the oldest franchise in the history of the NFL, but they may have been the most consistent, at least from the perspective of operating under certain guiding principles. They spent the first half of their existence as a laughingstock, but they were led consistently by the Rooney family.
Now three generations strong, the patriarchs remain the guiding force of the organization, and promulgate the vision through which business is done, which is demonstrated no better than in their hiring practices at the head coaching position, beginning with Chuck Noll in 1969, and continuing presently with Mike Tomlin.