Parcells left the Giants because he was burned out. He went to the Patriots and then the Jets.
Lombardi was burned out then went to Washington.
Stram spent some time as a commentator before going to the Saints.
By 1969, Jack, Lombardi's health was not in the best place. In fact, one of the major reasons why he retired from Packers after winning SB II was due to his increasing health problems.
Some of Lombardi's biographers have stated he had cancer when he agrees to become Redskins HC before the 1969 season. Even though Lombardi led Redskins to their first winning season, (7-5-2) in 13 seasons, the collective, cumulative stress hurt and damaged his precarious health even more.
Hank Schramm likely would have succeeded in his 5-year plan to rebuild the Saints team, but taking into consideration how impatient Mecom was and maybe how the game had sort of passed Hank, he never was around to see the fruition of his rebuilding program.