Coaching in the NFL isn’t an easy job. But there are certain guys who stand above the rest and have sustained periods of success. And it doesn’t always happen right away. Tom Landry, one of the best coaches of all time, went 0-11-1 in his first season with the Dallas Cowboys; Bill Parcells was 3-12-1 in his first season with the New York Giants; and even the great Bill Walsh was 2-14 with the San Francisco 49ers in 1979.