As he has done for most of his career when healthy, Stafford was again very productive this year. With 15 starts under his belt, he has over 4,400 yards and 30 total touchdowns. However, he also has completed less than 60 percent of his passes, thrown 19 interceptions and fumbled 12 times.
Stafford's inconsistencies have played a major role in the downfall of the Lions this year.
Even though he has repeatedly rebuked criticism of his mechanics since entering the league, something that the Lions coaching staff have supported him on, the issue does appear to lie in his discipline, both physically and mentally.
Mechanics play a major role in how accurately a quarterback can throw the ball. When Stafford neglects his mechanics, his accuracy suffers. A lack of accuracy and bad decision-making will doom even the most physically talented quarterbacks.
Stafford has one of the best arms in the NFL physically, but he hasn't shown the commitment to his craft to build on it. This has led to him throwing 19 interceptions on the season, but it has also caused him to miss throws he should make and throw passes straight to defenders that were dropped.
Even last week against the Baltimore Ravens, when the Ravens showed very little on offense to suggest they could survive without turnovers, Stafford's lack of discipline was on display. He forced a pass over the middle of the field that was intercepted with ease by Daryl Smith. Neither of his receivers in the area were close to the football, and he only attempted the pass because he was willing to side-arm it without a strong base beneath him.
Most of the better quarterbacks in the NFL would never have attempted that pass. Those willing would likely only do it in specific situations. Situations that made them desperate for points in a short time.
Although they are not as good as they were last season, the Ravens do at least have a good defense and an aura that comes with being the reigning Super Bowl champions.
The New York Giants are also recent Super Bowl champions, but their defense really shouldn't match up well to what the Lions try to do on offense.
Stafford completed just 25 of 42 passes for 222 yards, no touchdowns and two interceptions in this game.
The Lions lost by just three points, so those two interceptions proved to be crucial.
His first interception came late in the second quarter when the Lions were driving for a tying touchdown. There were 53 seconds left in the half, but the Lions had just been penalised so that they were facing a 2nd-and-17.
Stafford drops into a clean pocket. His offensive tackles keep the edge-rushers moving down the field, so Stafford smartly steps up in the pocket. While he has comfortably managed the pocket, he has focused on just one receiver ever since he received the snap. It appears that Stafford predetermined where he was going with the football, which is always very dangerous.
Notably, Justin Tuck isn't rushing the passer. Instead he is holding the offensive lineman away from his body and watching Stafford's eyes.
Joseph Fauria is the receiver Stafford is staring down. He is well covered, but he is also a big-bodied tight end who has the ability to hold off the defensive back and win at the catch point.
Often, when passes are tipped at the line of scrimmage, it is just bad luck. However, there are also times when the quarterback must be aware of what the defensive linemen are doing. As Stafford begins his throwing motion, Tuck is already leaping into the air. He is directly between Fauria and his quarterback, so Stafford should see him.
He has time to bring the ball back and adjust in the pocket to find Fauria or another receiver, but instead he lets the ball go regardless.
Tuck comes away with a relatively easy interception that sets up the Giants offense at midfield.
Even if the Lions hadn't scored a touchdown on this drive, they were close enough to field-goal range to cut down the Giants' lead. Instead, because of Stafford's decision, the Giants took over at midfield and extended their lead with a field goal before halftime.
Stafford's first interception was bad. It hurt the offense when it could have made a statement for the team before halftime.
However, the second interception had a much greater impact on the game.
With five minutes left, the Lions were leading by seven points. Although they were trying to run out the clock, they had no back besides Stafford in the shotgun. That was because it was 3rd-and-7 deep in Lions territory. Throwing here is not a bad decision, even if the lack of a play-action threat seemed misguided.
The Giants only rush three defenders, and the left defensive end rushes inside the right offensive tackle. This means that Stafford should adjust slightly to his right where the space is. He does that while keeping his eyes downfield.
To this point in the play, Stafford has made only good decisions.
He makes another good decision as he identifies Fauria running an out route past the first-down marker. Fauria is coming out of his route as Stafford leaves the pocket. Fauria creates some separation coming out of his route, and his 6'7" frame gives him a massive advantage over the defensive back trying to stop him.
Fauria in this situation gives Stafford a huge throwing window. He has a margin for error with his accuracy that most quarterbacks aren't afforded.
In spite of Fauria's huge catch radius and the window he has created, Stafford still manages to overthrow him. He gives his tight end a chance, but it's only a chance to make an incredibly difficult catch. Fauria fully extends and tries to bring the ball in with his fingers, but instead it is tipped into the air for the Giants to catch deep in Lions territory.
Not only does the turnover set up the Giants to score, they immediately take advantage on the return to tie the game at 20-20.
Stafford cannot be blamed for the loss to the Giants or for all of the Lions' failings as a whole for the season. But the two interceptions from this game show how little he has developed in recent seasons. If he was to become an elite quarterback, he needed to eradicate these issues from his game.
As with any offensive-inclined team in the NFL, the Lions will go only as far as Stafford can take them. For that reason, much of the blame for their failings will be placed at his feet.
More important than handing out blame is figuring out why the Lions haven't fulfilled their potential.
It's clear that Stafford has the talent to be an elite quarterback and the pieces are around him for them to be a playoff team. Is it coaching? Is it the culture of the franchise? Is it the players in the locker room?
Those questions won't be answered for some time, if at all. It's unlikely that the current coaching staff is around much longer to further examine them, but Stafford is guaranteed to be the team's franchise quarterback if healthy for the foreseeable future because of his contract situation.
Therefore, his flaws are now the focus for this franchise. Much like what the Chicago Bears did with Marc Trestman, the Lions need to find someone who can get the most out of the quarterbacks on their roster.