Grant Cohn: Ranking all the NFL head coaches

This is my comprehensive, highly-subjective ranking of all 32 NFL head coaches, arranged in ascending order and grouped into four tiers. Note: There are only a few accomplished head coaches because owners regularly fire coaches. And there are significantly fewer exceptional coaches in the NFL than in college football because college coaches aren't restricted to a draft and a salary cap.

Tier 1: The unproven.

These coaches have accomplished nothing. But they have high hopes because they're new and their owners have invested a lot of money in them and their staffs. They could succeed or not. The jury is still out on them. It's impossible to rate them at this point.

32. Anthony Lynn, Los Angeles Chargers. First season as a head coach. Fourteen games of experience as an offensive coordinator. Run-game specialist.

31. Vance Joseph, Denver Broncos. First season as a head coach. One season of experience as a defensive coordinator. Defensive-backfield specialist.

30. Sean McVay, Los Angeles Rams. First season as a head coach. Three years of experience as an offensive coordinator. The youngest head coach in NFL history. Extremely bright and creative.

29. Sean McDermott, Buffalo Bills. First season as a head coach. Eight seasons of experience as a defensive coordinator. One Super Bowl appearance in 2016 with the Carolina Panthers.

28. Kyle Shanahan, San Francisco 49ers. First season as a head coach. Nine seasons of experience as an offensive coordinator. One Super Bowl appearance in 2017 with the Atlanta Falcons. Winner of last season's Assistant Coach of the Year Award. One of the sharpest offensive minds in the league.

27. Doug Pederson, Philadelphia Eagles. Second season as a head coach. Won seven games and missed the playoffs during his first season.

26. Dirk Koetter, Tampa Bay Buccaneers. Second season as a head coach. Won nine games and missed the playoffs during his first season.

25. Adam Gase, Miami Dolphins. Second season as a head coach. Won 10 games and made a playoff appearance during his first season.

24. Ben McAdoo, New York Giants. Second season as a head coach. Won 11 games and made a playoff appearance during his first season.

Tier 2: The incomplete.

These coaches have more than one season of experience, but not enough to make a definitive judgment about them.

23. Hue Jackson, Cleveland Browns. Third season as a head coach. Lost 15 games in 2016, which may not be his fault. He works for the worst organization and the worst front office in the NFL, and he coaches the least-talented roster.

22. Doug Marrone, Jacksonville Jaguars. Third season a head coach. Quit after his second season with the Bills even though he won nine games. His potential for success with the Jaguars is limited by his quarterback, Blake Bortles, who is one of the worst in the NFL.

21. Todd Bowles, New York Jets. Third season as a head coach. Won 10 games his first season but missed the playoffs, then won just five games during his second season. Now, the Jets front office has dismantled the roster, and the team seems to be tanking for the top pick in next year's draft so they can get a franchise quarterback. Bowles probably won't be around to coach that quarterback in 2018. Bowles is on the hot seat.

20. Jay Gruden, Washington Redskins. Fourth season as a head coach. One playoff appearance in 2015. Zero playoff wins. Limited by a volatile organization that fired their general manager this offseason and still has not signed their starting quarterback to a long-term deal.

19. Mike Zimmer, Minnesota Vikings. Fourth season as a head coach. One playoff appearance in 2015. Zero playoff wins. Limited by a roster that is always in a state of flux and turnover.

18. Bill O'Brien, Houston Texans. Fourth season as a head coach. Two playoff appearances. One playoff win. O'Brien is an offensive coach who's aided by a great defense. His offense is never good. He constantly shuffles quarterbacks.

17. Mike Mularkey, Tennessee Titans. Sixth season as a head coach. Zero playoff appearances. Limited in the past by poor quarterbacks, but now he has a very good one — Marcus Mariota — and the Titans are on the rise. Mularkey has the best chance of the coaches in this group to succeed.

Tier 3: The unimpressive.

These coaches have been around for a while and have done nothing to advance themselves to a higher level.

16. Chuck Pagano, Indianapolis Colts. Sixth season as a head coach. Three playoff wins, but no playoff appearances the past two seasons. Pagano has underachieved with arguably the most talented young quarterback in the NFL — Andrew Luck. The Colts probably will fire Pagano if he misses the playoffs for a third-straight year.

15. Jim Caldwell, Detroit Lions. Seventh season as a head coach. Four playoff appearances. Two playoff wins, but none since 2010 when Peyton Manning was his quarterback. The Lions probably will fire Caldwell if he doesn't win a playoff game next season.

14. Marvin Lewis, Cincinnati Bengals. Fifteenth season as a head coach. Seven playoff appearances. Zero playoff wins. The Bengals probably will let his contract expire unless he wins at least one playoff game next season.

Tier 4: The accomplished.

These coaches have stripes on their sleeves, but also have flaws or problems.

13. Sean Payton, New Orleans Saints. Eleventh season as a head coach. One Super Bowl victory in 2010. Zero playoff appearances the past three seasons. At one point, Payton was the brilliant young coach in the league. Now, he looks tired, old and confused, and he has turned into a joke. He's a one-dimensional coach whose defense and run game always stink, and his reputation is tarnished and scandal-ridden since Bounty Gate in 2012. He is not just a bad coach — he's a bad guy. When the Saints fire him at the end of this season, he might pop up again as an offensive coordinator, but he never again will he be a head coach.

12. John Harbaugh, Baltimore Ravens. Tenth season as a head coach. One Super Bowl victory in 2013. Zero playoff appearances the past two seasons. Harbaugh's flaw is his offense — he's had five offensive coordinators the past five seasons. Last season, his offense passed the ball 679 times – tops in the NFL. You can't win when you pass that much.

11. Ron Rivera, Carolina Panthers. Seventh season as a head coach. One Super Bowl appearance two seasons ago. Finished fourth in the NFC South last season. Rivera's problem is his front office, which has failed to replace key players who have left the team during free agency, and has failed to acquire quality offensive linemen to protect Cam Newton.

10. Dan Quinn, Atlanta Falcons. Third season as a head coach. One Super Bowl appearance last season, during which he blew a 25-point lead in the second half and did nothing to stop the hemorrhaging. Failed to make an adjustment on defense, and failed to tell his offensive coordinator, Kyle Shanahan, to run the ball more. Quinn just watched his team collapse. This makes you wonder if he really is a bright, up-and-coming coach, or merely a cheap knockoff of his mentor — Pete Carroll.

9. John Fox, Chicago Bears. Sixteenth season as a head coach. Two Super Bowl appearances. Fox has a history of making teams contenders very quickly, but he hasn't made the Bears contenders yet because their roster is so bad.

8. Jack Del Rio, Oakland Raiders. Twelfth season as a head coach. Three playoff appearances, including one last season. Del Rio took over a 3-win Raiders team, and turned them into a 12-win team just two years later. A lot of people expect him to lead the Raiders to the AFC Championship next season. His stock is very high because he's a terrific leader, but he struggles to hire quality coordinators. That's his flaw. In 2015 he made his defensive coordinator Ken Norton Jr, who had no coordinator experience. And this offseason Del Rio made his offensive coordinator Todd Downing, who also had no coordinator experience.

7. Pete Carroll, Seattle Seahawks. Twelfth season as a head coach. One Super Bowl victory in 2014, and one Super Bowl meltdown in 2015. He's notorious for his meltdown. He had the ball at his opponent's 1, second-and-goal, trailing by four points with 26 seconds left on the clock and one timeout left. Carroll also had the best running back in the league — Marshawn Lynch — who was unstoppable in that game. Instead of handing the ball to Lynch or calling a timeout to decide what to do, Carroll ceded power to his offensive coordinator and let him decide. The offensive coordinator called a pass which got intercepted and the Seahawks lost. A better head coach would have taken control in that situation.

6. Mike Tomlin, Pittsburgh Steelers. Eleventh season as a head coach. One Super Bowl victory in 2009. Tomlin is a highly successful coach whose winning percentage in the regular season is .644. But recently, he has had to deal with suspensions to key player on his offense — running back Le'Veon Bell and wide receiver Martavis Bryant. Tomlin has to do a better job controlling his troops.

5. Mike McCarthy, Green Bay Packers. Twelfth season as a head coach. One Super Bowl victory in 2011. McCarthy has not returned to the Super Bowl since then even though he has one of the best quarterbacks of all time — Aaron Rodgers. If McCarthy doesn't make the Super Bowl next season, the Packers may fire him, which may not be so fair. McCarthy's problem is his front office. It almost never signs impact free agents. This has hurt the Packers defense in particular.

4. Jason Garrett, Dallas Cowboys. Eighth season as a head coach. Two playoff appearances. Thirteen wins last season. Garrett is a terrific head coach with a terrific staff of assistants. His problem is his boss — Cowboys owner Jerry Jones. Garrett constantly has to work around Jones' risky draft picks and signings. The past two years, Jones has acquired six defensive players who were known to have baggage and have been suspended, are suspended or will be suspended next year. Those players are Rolando McClain, Greg Hardy, Randy Gregory, Demarcus Lawrence and David Irving. Jones keeps making the Al-Davis mistake thinking he can corral these problem players.

3. Andy Reid, Kansas City Chiefs. Nineteenth season as a head coach. Twelve playoff appearances. One Super Bowl appearance. Reid is one of the most creative coaches in the NFL – he's brilliant at making game plans. If he has an extra week to prepare for an opponent, he's almost unbeatable. But his flaw is his conservative nature. He doesn't want to throw deep. He wants 13-play drives, which are almost impossible to pull off more than a couple of times per game. Reid's conservative offensive always will prevent him from winning a Super Bowl.

2. Bruce Arians, Arizona Cardinals. Fifth season as a head coach. Two playoff appearances. One Conference Championship appearance. Of all the coaches in this group, Arians is the most creative. And he is not conservative like Reid. Arians is one of the most aggressive deep-pass play callers in the NFL, and he has done great things with the Cardinals offense. His problem is his quarterback — Carson Palmer. When Palmer goes south, Arians' opportunities for success go south. The organization should have found a replacement for Palmer by now, but it has not.

Tier 5: The exceptional.

1. Bill Belichick, New England Patriots. Five Super Bowl victories. Belichick is in a tier by himself. He is one of the greatest coaches of all time and the only coach currently in the league who can replace great players with lesser players and still win. He lost Rob Gronkowski to a season-ending injury last year and still won the Super Bowl. Belichick is that brilliant.