Leadership isn't always the easiest thing to define.

It's hard to delineate the characteristics that make up someone who is looked upon by his peers as the one to steer the collective attitude—the mindset during the tough times.

But that's exactly how Alex Smith's teammates were looking at him early in the season, when the Chiefs were struggling and not living up to the expectations of both themselves and the fans—that this was supposed to be the best team in the three years of the John Dorsey-Andy Reid-led era.

Fans and pundits don't get to see how Smith carried himself every day he came to work, and not just when the cameras were in his face, but also the other times as well.

It's the same. He's the same guy all of the time, and it's all business.

People don't get to see Smith meeting with his starting center each week to go over more than 100 third-down plays and the defensive looks they may see against each of them.

These meetings are after the "normal" workday.

They aren't in that room to see Smith work with either rookie Mitch Morse or second-year player Zach Fulton, who has now started at center three times in his career dating back to his days at the University of Tennessee. But ask either of those players about what it's like to work with Smith and you'll get a similar response, and the word "leader" or "leadership" will be among the consistent comments.

Smith isn't the rah-rah type, but look no further than his postgame comments against the Minnesota Vikings back in Week 6 to see where his head was at just moments after a devastating defeat—the fifth one in a row in a season that began with such high expectations.

"As bad as it stings today, there's going to be a game next Sunday," Smith said. "We're going to be out there and we're going to put it on the line. As dark as it is, if you want to sulk, there's no time for that. The ball keeps moving." 

This quote was about 30 minutes after the end of that game, which was a frustrating one that saw penalties, turnovers and missed opportunities hamper a team that was desperately looking for a win to get back on track.

There wasn't any time for Smith to blow off steam or get a bunch of his thoughts together. The comments were real and the message was genuine, and it was one of leadership from Smith.

The next week was against the Pittsburgh Steelers and he'd be without his No. 1 target in Jeremy Maclin, who suffered a concussion in the game against the Vikings the week before.

They had lost five straight and Smith and company would look to get back on track with a group of young receivers and a running backs group that had only been without Jamaal Charles for a week.

It would also be the fourth starting combination along the offensive line in seven games.

After five straight losses, Smith led the Chiefs to a victory over the Pittsburgh Steelers and then 10 more consecutive wins after that.

 "When he started out, we said he was going to be a top-10 quarterback," general manager John Dorsey explained. "There were certain categories where he was a top-10 quarterback this year."

Smith finished in the top 10 in the NFL in completion percentage (65.3 percent), 25-plus-yard pass plays (32) and interception percentage (1.5 percent).

"When you have a guy like that, he's moving the chains," Dorsey added. "As I look at it, I hear people say 'Well, he's a game manager.' No he's not.

"He's a game winner. And to me, at the end of the day, you are your record—wins and losses, and he's a game winner."

Smith has 30 regular season wins in his first three years as the quarterback of the Chiefs, which is the most for any player in his first three years with the franchise.

Here are some other franchise records Smith now holds:

Passer rating: 92.5

Completion percentage: 63.66

Consecutive passes without INT: 312

It's also worth noting that Smith was better on the road than he was at home.

When he was on the road, Smith threw less interceptions, had a higher completion percentage, had a better yards-per-attempt average and the offense scored more points.

Here's the breakdown:

This is the first time in Smith's career that he's had any kind of continuity among his coaching staff. He had the same head coach, offensive coordinator and quarterbacks coach in each of his first three seasons in Kansas City.

While that will change a bit now that Doug Pederson has moved on to the Philadelphia Eagles, Smith will still have two familiar faces in Matt Nagy and Brad Childress to serve as co-offensive coordinators.

But most importantly, it'll be the same offense again for Smith.

 "I think Andy's opened up the book to him, and I think he's digested that book," Dorsey explained. "Andy's giving him the freedom now to do the check-with-me at the line—to make certain audibles against certain defenses. That's a mark of a good quarterback.

"Once he sees the defense, he's going to put the offense in proper position to move the chains, and that's what he did. Whether it be his feet, his arms or his brain—he's giving the team a chance to win."

One of those times that Smith saw the play and checked it was at home against the San Diego Chargers, when he saw Albert Wilson in one-on-one coverage to the outside and read an all-out blitz from the Chargers defense.

He made the check and the result was a 44-yard touchdown—the only touchdown scored by either team in the game—and it proved to be the difference in the Chiefs picking up their seventh straight victory.

Perhaps what fans might remember more from that day was an unusual display of fire from Smith, who after a first-down run, felt as if a Chargers defensive back was "head hunting" a bit.

"He showed a lot of fire on that play," Chiefs coach Andy Reid noted. "His legs have helped us and I know he's getting up there (in age) a little bit, but he knows how to protect himself when he goes down."

When asked in the locker room after the game, Smith's teammates said they loved the fire he showed because it allowed everyone else to see what they already see in how he prepares for his craft each and every week.

It's one of the defining pictures of the season.

For the second straight season, Smith broke his personal career best for yards rushing in a season with 498, which was third best among quarterbacks in the NFL.

His ability to take off and run to pick up chunks of yards proved to be one of the main offensive weapons for the Chiefs down the stretch.

Through the air, Smith and veteran Jeremy Maclin developed a nice chemistry in their first year together.

Maclin said back during OTAs that he and Smith were off to the best start of any quarterback he'd had in his career, which is one of the reasons he finished with more than 1,000 yards for the second time in his career.

"It's all about trust. He trusts me; I trust him," Maclin said. "We're able to get together and communicate and talk about certain things on the football field. I think that's the type of relationship you want with your quarterback."

The relationship Smith has with his teammates is one that is undeniably built upon a respect and understanding of who they can look towards for leadership when things aren't going well.

Smith is that guy.

From 1-5 to the first playoff win in more than two decades, Smith's place in franchise history is long from set in stone, but the 2015 chapter showed us what he's about.