In Gailey's three years as the head coach, the Bills went 16-32 overall and 4-14 in the AFC East.
His voice trembling, Gailey delivered a heartfelt statement to Buffalo media (per BuffaloBills.com):
"The first thing I wanted to say was thanks to the Bills organization, to Buddy [Nix] and Mr. Wilson for the opportunity. I understand this is a business. We didn't get the job done. I've been called two other times to get things turned around, was able to do it. We weren't able to get this one done soon enough, and I understand that completely.
"I want to thank the fans, great Buffalo fans, great football town. These are loyal, loyal fans, and I understand that. I think that the next staff will have a great opportunity for success and to make this another great football franchise.
"This'll probably be, and I say probably, but I think it will be the first place that's ever fired me that I'll pull for. Thank you.
Now that he has been relieved of his duties, the Bills must move forward. Here's five steps they can take to turn the tide on their struggling franchise.
General manager Buddy Nix stood by Gailey all season long and his reasoning was the same from beginning to end.
"The age-old thing—and they’ve done it around here for years—is to start over about every three years," he told The Buffalo News back in November. "What that does is make damn sure you don't make it. ...You change every three years and you never quite get there. That's my take."
The Bills need to also make sure that their next guy is the guy.
It's not a shock that the team is moving in another direction at head coach once again, but it wouldn't have been a surprise if the Bills had stuck with Gailey, either. Gailey had three years to take a perennial losing team and turn it into a winner. We heard Redskins head coach Mike Shanahan say he told Redskins owner Dan Snyder it would take at least five years to rebuild the Redskins.
There is talent on the roster, but whoever the next head coach is needs to get more than just a few years to get the team on the right track. That being said, the next head coach also needs to win early to prove worthy of a long-term tenure as the front man.
The Buffalo Bills are riding a 13-year playoff drought, which roughly coincides with the last time the team had a playoff-caliber quarterback.
We have known for a long time that quarterback Ryan Fitzpatrick was not the team's answer at the game's most important position—perhaps ever since that bogus six-year contract extension.
Clichés only go so far in saying that the NFL has become a passing-dominated league. Of the 12 playoff teams, 10 rank in the top half of the league in passer rating. The Bills ranked 19th this season, and Fitzpatrick's 16 interceptions ranked ninth-most in the NFL among starting quarterbacks after finishing with a league-high 23 interceptions in 2011.
Efficiency at the quarterback position has always been the difference between championship contenders and pretenders. Without it, the Bills will continue to be muddled in the same mediocrity their quarterbacks have suffered, regardless of who the head coach is next year.
Nix repeatedly asserted during the season that the Bills were looking to find a franchise quarterback (per Pro Football Talk) this offseason. In retrospect, those comments could be seen as a lure to head coach prospects to come to Buffalo so they can build the franchise starting with a franchise quarterback.
Gailey is not the only one out of a job. His entire staff was taken out along with him.
This is a pretty typical part of the process, but it means the Bills will be moving forward with brand new philosophies on both sides of the ball.
That leaves the futures of a lot of players in jeopardy, as well. How will the new coaches' schemes fit with the players already on the roster? Which players will have roles and which players will find themselves as square pegs being jammed into a round hole?
It can take a long time to build a roster that fits the scheme. It can happen in one offseason, but rarely is that the case. It will help if the Bills find a coaching staff that shares similar philosophies to what the Bills employed last season, but to what degree? That remains to be seen.
This is probably part of the reason why Nix reiterated time and time again his desire to not change head coaches every three years. The Bills will need to build toward an end game, potentially a different one than what they'd been building toward since 2010.
The Bills have holes, but by and large, they have talent on both sides of the ball.
Their shortcomings are an indictment of the coaching staff's inability to utilize that talent.
The misuse of talent starts with running back C.J. Spiller, as the explosive back was held down by limited opportunities. He carried the ball more than 20 times in just three games this season.
Beyond Spiller, tight end Scott Chandler and wide receivers Stevie Johnson and Donald Jones also give the Bills some talent at skill positions on offense. The offensive line has been one of the best in football in terms of pressure on the quarterback and sack percentage over the past two years.
On defense, the Bills have spent a lot of money on the front seven, and although Mario Williams and Mark Anderson aren't All-Star pass-rushers off the edge, they are athletically talented players and could be even better if used properly.
The Bills' most glaring needs are for a quarterback, wide receiver, weakside linebacker, cornerback and a safety. While those five needs may not all be filled this offseason, there are teams with many more holes to fill than the Bills.
Bills fans are tired of losing. Who can blame them? It's been eight years since the Bills had a winning record and 13 years since they made the playoffs—the longest such active streak in the NFL.
At least they'll have a team to root for over the next 10 years (or so), but they understandably want their team to be back in the mix for a championship before the end of the lease agreement.
If Nix wants the fans to stop complaining about "staying the course," (per The Buffalo News) he and the Bills need to prove that the course is worth staying on.
The Bills made it a serious point to win their fans over last offseason by signing Mario Williams to a top-dollar contract, fulfilling a big need at defensive end with one of the consensus best players available in free agency.
Moves like that help if the team is winning, but otherwise it looks like the team is not spending wisely.
The best way to win back the fans is by winning and that will only happen if the Bills follow all the steps to success.
Erik Frenz is the AFC East lead blogger for Bleacher Report. Be sure to follow Erik on Twitter and "like" the AFC East blog on Facebook to keep up with all the updates. Unless specified otherwise, all quotes are obtained firsthand or via team press releases.