ESPN.com has been counting down the top head coaches in NFL history. You can vote for your favorite here.

But if there are "greatest" NFL head coaches, there also have to be "worst" NFL head coaches. Let's not forget them -- even though the fans of the teams they coached probably want to.

Here are the 14 worst head coaches in NFL history. The yin to the Walsh-Noll-Landry yang.

David Shula -- Shula, Don Shula's son, is proof that sometimes the apple does fall far from the tree. So far that the apple can then also roll down a muddy hill, and then across a ditch and onto a road, where it is run over by a steamroller and a marching band, its splattered chunks rotting in the sun as they are picked at by vermin. That was David Shula's NFL coaching tenure. Hired by the Bengals at age 33 in 1992, he coached four and a half seasons and finished 19-52. This is the official pose of his NFL coaching career. He is now a steakhouse executive.

Bert Bell -- Bert Bell had a 10-46-2 record as an NFL coach for five-plus seasons with the Eagles and Steelers and, at .179, has the worst winning percentage in NFL history for any head coach who lasted 50 games -- well ahead of (behind?) Shula's .268. However, following his failed coaching career, Bell became NFL commissioner and was later enshrined in the Pro Football Hall of Fame. He can serve as a role model to other failed NFL head coaches. Perhaps one day we will see NFL commissioner Rex Ryan.

Romeo Crennel -- No list of terrible NFL head coaches would be complete without a mangled branch of Bill Belichick's diseased and poisonous coaching tree -- and because Charlie Weis has mercifully never been an NFL head coach, the honor goes to Crennel. After failing in Cleveland at 24-40 from 2005 to 2008, the Chiefs inconceivably gave Crennel another shot three years later and he went 4-15 and routinely delivered quotes such as this one following Kansas City's 2012 Week 2 loss: "I thought that we would be better, and we're not. So we have to try and figure out what that is. From what I've seen, if we do what we're supposed to do, then we would be better." Definitely. That's some good coaching insight. It's surprising Crennel didn't win more.

Cam Cameron -- This is a list of failed head coaches in the NFL, so we won't mention Cameron's 18-37 record as a college head coach with the Indiana Hoosiers from 1997 to 2001. Also, we won't mention the fact that the Baltimore Ravens instantly developed a Super Bowl-caliber offense upon jettisoning Cameron as an assistant coach late last season. We'll just mention the fact that Cameron went 1-15 as head coach of the Dolphins in 2007.

Rich Kotite -- In 1995, Jets owner Leon Hess fired head coach Pete Carroll and installed Rich Kotite as head coach and general manager. "This is my decision,'' Hess said at the news conference announcing the move. "At 80, I'm entitled to some enjoyment out of this team and that means winning. Rich Kotite in my opinion is one of those men who can make a winning team out of the Jets." What came next is another long chapter in depressing Jets history.

Phil Handler -- Handler coached 38 games between 1943 and 1951 and posted a 4-34 record. He opened his career 0-23. Hey, that means he finished 4-11. Huh. Maybe he was starting to get the hang of it at the end.

Hilariously named coaches -- If you wanted to lose in olden times NFL, there was no better way to do it than hire a man with an entertaining name. Here are coaches who finished their careers with records below .500: Shorty Barr, Dim Batterson, Bull Behman, Untz Brewer, Coonie Checkaye, Dutch Clark, Al Cornsweet, Luby DiMielo, Turk Edwards, Tex Grigg, Hinkey Haines, Pop Ivy, Homer Rice, Clipper Smith, Bulldog Turner, Hoge Workman.

Marty Mornhinweg -- Mornhinweg captained the Lions to a 5-27 record between 2001 and 2002. That's bad. This is really bad: Week 12 of the 2002 season against the rival Bears. Game goes into overtime. The Lions win the toss. Mornhinweg elects to kick the ball away. Detroit never gets the ball back because the Bears move the ball down the field and kick a game-winning field goal. Mornhinweged.

Rod Marinelli -- You go 0-and-the-entire-season with a non-expansion team, you make a list like this. Those are the rules. At least Marinelli delivered some great quotes during his 10-38, three-year term with the Lions, such as: "You're in this dark tunnel and you've got no way out, you're waiting for light, and you see that light, what do you do? What do you do? You start digging and getting out. … It's dark and I'm going to dig through. My shovel is sharp and my pick is sharp and my will is outstanding."

Pretty much every Bills coach -- Here we go:

Buster Ramsey (1960-61): 11-16-1

Joe Collier (1966-68): 13-16-1

Harvey Johnson (1968, 1971): 2-23-1

John Rauch (1969-70): 7-20-1

Jim Ringo (1976-77): 3-20

Kay Stephenson (1983-85): 10-26

Hank Bullough (1985-86): 4-17

Gregg Williams (2001-03): 17-31

Mike Mularkey (2004-05): 14-18

Dick Jauron (2006-09): 24-33

Chan Gailey (2010-12): 16-32

Best of luck, Doug Marrone!

Bobby Petrino -- Going 3-10 wouldn't be enough to make a list like this. But quitting midseason and informing your players by leaving notes in their lockers? Yeah. That does it. If only Petrino's Atlanta departure was the most embarrassing part of his coaching career.

Abe Gibron -- As head coach of the Bears from 1972 to 1974, Gibron posted an 11-30-1 record. He coached 24 seasons in the NFL in some capacity and his teams won a total of one playoff game. He did, however, look awesome in late-'70s Tampa casual attire.

Norv Turner -- With a .483 winning percentage over 237 games, the former Redskins, Raiders and Chargers head man coached more games than any other head coach in NFL history with a sub-.500 record. Turner's place here is a lifetime achievement award for miraculously maintaining employment for 15 years.

Faye Abbott -- Abbott coached the NFL's Dayton Triangles in 1933 and 1934 and has the distinction of coaching the most games in NFL history without a win. Over his 0-13 tenure, the Triangles scored 16 points and were shut out 11 times. Abbott is not generally regarded as an offensive mastermind. You know, like Norv Turner.