The NFL can be quite harsh for some people. To take part in the world's best football competition, you have to be prepared for anything. Especially, to overcome every obstacle along the way. Results and performances can be decisive, and a setback can wipe out any previous achievements.

That rule applies to anyone in the league. Every player, no matter the position nor the status, and all coaches have to deal with the challenge of working under pressure continuously. Throughout the history of the competition, many have come and gone in a blink of an eye.

Not many people last long in the managerial role, one of the most unstable in this sport. If things don't work, they are usually the first to blame, and most of the time they don't get a chance to prove those arguments wrong. However, some head coaches were the exception and retained their positions for a long time, cementing a legacy in the sport. Check out who were five of them.

Bill Belichick (Cleveland Browns - New England Patriots)

26 seasons*

The iconic New England Patriots head coach is the only one from this list who is still working in the NFL. Bill Belichick is already a legend in the Foxborough franchise, where he took over as the head coach in the 2000 season following a five-year stint with the Cleveland Browns. Being with the Patriots for 21 years so far, he is one of the very few to have lasted for such a long time in charge of the same team. Under his guidance, the Pats claimed a record six Super Bowl rings, building a dynasty with one of the best quarterbacks ever, Tom Brady.

*Still serving as NFL coach

Tom Landry (Dallas Cowboys)

29 seasons

The first coach in the Cowboys' history, Landry was in charge of the team for 29 straight years from 1960 to 1988, an NFL record. During that successful spell, Dallas won two Super Bowls, five NFC championships, and 13 divisional titles. Moreover, he also holds the record for the most consecutive winning seasons (20).

Don Shula (Baltimore Colts - Miami Dolphins)

33 seasons

The Miami Dolphins and NFL legend served as a coach for 33 years, from 1963 to 1995. He began his career with the Baltimore Colts, who made it to their first Super Bowl ever with him, but he spent most of his coaching life in South Florida, where he will be always remembered for his 26-year tenure. Under his leadership, Miami won two Super Bowls in a row, which remain their only championships in history. The first of those, in 1972, was the only perfect season in the league so far. Don Shula is also the winningest coach in the NFL's history with 347 triumphs

Curly Lambeau (Green Bay Packers - Chicago Cardinals - Washington Redskins)

33 seasons

Co-founder of the Green Bay Packers, who named their stadium after him in 1965, Lambeau coached the team for 20 consecutive years from 1919 to 1949. In that span, the Packers won six NFL championships and amassed 200+ wins. After leaving Green Bay, he spent two seasons with the Chicago Cardinals and a further two with the Washington Redskins.

George Halas (Chicago Bears)

40 seasons

The longest-serving coach in the league's history, George Halas dedicated almost his entire life to the Chicago Bears, being founder and owner of the franchise. He served as a coach in four different stints, one from 1920 to 1929, then between 1933 and 1942, later in 1946 and 1955, and his final one in 1958 until 1967, winning six titles. One of the co-founders of the NFL, Halas' name will be always remembered in the sport's history.