Dan Quinn is talking about one of the great keys to success in the NFL, and it has nothing to do with offensive schemes designed by aerospace engineers or ego-fueled attempts to ignore maybe 100 years of professional football history and re-invent the wheel (hello, Chip Kelly).

It turns out the key to success in the NFL might be … (are you ready?) … effort.

I know. Pretty revolutionary stuff.

“When you demonstrate your effort to the guy next to you, that’s when it becomes rewarding,” Quinn said. “It’s like, ‘I’m not going to let you down.’ That’s when the respect comes. And when you go through some close games, you develop some toughness and you’re able to finish. The connection gets stronger, the toughness gets better, the confidence grows. I was hoping we would have some games early where we had the ability to demonstrate that, and we have.”

The Falcons are 2-0. They have won both games in the fourth quarter.

Maybe they should have hired Zig Ziglar years ago.

This is a team that was 10-22 over the past two seasons. That misery universally has been blamed on personnel (Thomas Dimitroff) and sideline mistakes (Mike Smith, coordinators). But the truth is, there were several games in which the Falcons just wilted. Let up. Quit. Players and coaches never would admit that effort sometimes was less than stellar as games worn on. They wouldn’t concede that in many games they were soft (and soft more often is a mindset than something that relates to physical size). But this was a horrible fourth-quarter team in 2013 and 2014, and it wasn’t just because somebody called the wrong play or drafted the wrong guy.

The Falcons’ defense allowed opponents an average of 4.4 points in the fourth quarter in 2010, which ranked second-best in the NFL. But they got worse in every season that followed:

2011: 4.6 points (ranking: fourth).

2012: 6.2 points (ranking: 15th).

2013: 7.9 points (ranking: 26th).

2014: 8.7 points (ranking: 32nd).

These are trends that lead to losses and get coaches fired. It did.

Through two games, the Falcons rank fourth best with only seven points allowed (3.5 per game) in the fourth quarter. They were outscored in the fourth quarter 139-91 last season and 266-184 in the past two years.

Conversely, they outscored opponents 175-131 in the first quarter in 2013 and 2014. But it turns out games aren’t won in the first quarter. Who knew?

“For whatever reason we weren’t able to finish last year,” said defensive tackle Jonathan Babineaux, who’s in his 11th season and is the senior member of the team with Roddy White. “Coach Quinn preaches finishing daily, so it’s always on our mind. We’re prepared for every situation. Like the other day we were talking about, ‘OK, we’re up by four points and the other team needs a touchdown in the last two minutes to win. What are we going to do?’”

So you weren’t prepared in the past?

“I think we prepared. But every coaching staff is different. With coach Quinn it’s more like a daily operation. It’s all about the ball and the finishing for us. We’re together. It’s about balling out for your brother.”

In the season opener, the Falcons blew a 20-3 lead to Philadelphia and were outplayed for much of the second half. But unlike the past two seasons, they didn’t collapse. They drove to two fourth-quarter field goals and held the Eagles to a missed field-goal attempt and an interception on their final two possessions.

Sunday at New York, they trailed the Giants 20-10 after three quarters. They outscored them 14-0 in the fourth. The last four New York possessions: fumble (sack/strip by Kroy Biermann), punt, punt, downs.

Quinn has created an atmosphere that has strengthened connections of coaches to players and players to players. He has depended on a select group of players who’d led by example in game-long effort, including Paul Worrilow, Justin Durant and Adrian Clayborn on defense, and White, Julio Jones and Matt Ryan on offense.

The Falcons haven’t had many bad guys or outright slugs (Ray Edwards). But they’ve been thin in guys who command accountability — and locker-room accountability has a greater impact and longer shelf life than a screaming coach.

Quinn said, “You can scare somebody and threaten them into, ‘You better play hard or else!’ But that’s just a good emergency brake. There’s another level you can go to that’s way more meaningful, and that’s when a person is doing it for himself and the other guy.”

Sounds simple. What took so long?