Twelve months ago, the answer to this question was incredibly simple and straightforward: Three games.
After Kevin Durant, Russell Westbrook and company took Game 1 of the 2012 NBA Finals from the Miami Heat, it appeared as if the consistent ascension of the OKC franchise would continue to increase at the same rate.
After the team's first season in Oklahoma City in 2008-09, the Thunder raised their status multiple levels in year two, not only finishing with a winning record but winning 50 games and pushing the eventual champion Lakers to six games in Round 1.
In 2010-11, the team again took a giant leap forward, advancing to the third round of the playoffs before again losing to the eventual champions; this time the Dallas Mavericks.
So, after that Game 1 finals win in 2012, it appeared that the Thunder would again win two more playoff series than the previous season.
The Heat went on to win the next four games, and Oklahoma City again had its season ended by the eventual NBA champions.
Still, optimism reigned supreme. Even if the Thunder's rate of growth slightly decreased in 2011-12, this was only natural as they climbed higher and higher into the NBA stratosphere of elites. And after losing in the NBA Finals, a championship in 2013 appeared inevitable, seeing as the team had improved significantly in each of the previous three seasons.
Even after a preseason trade that left the team without its explosive sixth-man in James Harden, the Thunder again improved.
They finished the 2012-13 regular season first in the Western Conference, their best seeding yet. Their 60-22 record was also a franchise best since moving to the southwest.
Russell Westbrook's torn meniscus during Round 1 effectively ended the team's 2013 title hopes. One could claim that Westbrook's injury simply delayed OKC's inevitable championship by one year. If you believe that, then you've also sufficiently answered the question that this article title poses: One year.
But championships are never inevitable, and there's no such thing as a "natural championship progression" in professional sports. The Miami Heat, Dallas Mavericks, Los Angeles Lakers, Boston Celtics and San Antonio Spurs—the last five NBA-title winners—all followed different trajectories.
In fact, the Thunder's model of winning, drafting elite players with high picks, growing together and getting better each year, is vastly different than any of the blueprints used by the aforementioned teams. The "naturalness" that OKC's model seems to inherently possess is in fact incredibly rare and therefore arguably unnatural.
Injury certainly ended any chance for the Thunder to win the 2013 NBA title, but was a title a realistic expectation to begin with?
The Oklahoma City roster underwent several minor tweaks between 2011-12 and 2012-13, but there was really only one change that mattered for the immediate future: James Harden was out, Kevin Martin was in.
During the regular season, this change did not hurt OKC. Harden's 16.9 points per game were accounted for, as Martin averaged 14 PPG and Serge Ibaka's scoring average increased from 9.1 to 13.2 PPG.
The playoffs, however, may not have treated this change so kindly.
Had the Thunder had a healthy Westbrook they would have almost certainly gotten to the Western Conference Finals. They were eliminated in five close games by the Memphis Grizzlies in Round 2, while Kevin Durant faced double-teams that Westbrook would have made impossible and while Reggie Jackson and Derek Fisher took the bulk of the shots that Westbrook wasn't there to take.
In the conference finals, the Thunder would have faced the Spurs, the team they beat to reach the finals in 2012.
The Spurs play perfect team defense and are simply not beaten by role players over a seven-game series. They make it incredibly tough on options No. 1 and 2 with elite defenders, double-teams and physicality that somehow doesn't result in fouls.
If these opposing stars are smart, they give the ball up, but San Antonio rotates well enough to close out on spot-up shooters, defend off-ball cuts to the hoop and rebound missed shots.
The only way to beat them is to have a third option who can break down the defense and make plays. James Harden was that guy last year, as he used his exceptional quickness, skill, strength and savvy to average 18.5 PPG against the Spurs on 49.3 percent shooting.
To beat San Antonio without a third option like this would have been unlikely at best, impossible at worst. And if the Thunder did break through to the finals, they would have again met Miami, who beat them in five games last year.
Without Harden, beating the Heat was simply not a realistic possibility for the Thunder. Durant and Westbrook had enormous performances in the 2012 Finals, combining to average 57 points. That was largely due to the attention that Harden drew when on the floor.
If the Thunder were to face Miami without Harden, the Heat wouldn't even have to focus more attention on Durant and Westbrook. They'd let them average 57 again—60 even—but simply have an easier time containing everyone else.
Of course, games are not played on paper, as the current NBA Finals are proving.
The Heat don't look as dominant as they did last season, and that isn't only because of San Antonio. Dwyane Wade and Chris Bosh are not the forces they once were, and whether health is culprit or not is irrelevant; stuff happens.
If the Thunder return with the exact same roster next season, they could end up winning a title. Sure, they don't have James Harden, but the Spurs are old and fragile. They could break down physically. The Heat have been pushed to the brink in the Eastern Conference Finals two years running; they could lose a Game 7 next year.
Combining all the uncertainty surrounding the NBA Playoffs with the certainty surrounding the extremely high level of talent on Oklahoma City's roster, the Thunder should be considered legitimate title contenders next season.
However, the events that have occurred over the last 12 months teach us a valuable lesson: Just because a team appears to be headed upwards doesn't mean they haven't reached the peak.
The Thunder had to get rid of Harden because they couldn't afford to keep him, Durant, Westbrook and Ibaka. That's not their fault; there's a salary cap. Stuff happens.
But championships are promised to no one. Maybe the Thunder continue to draft well, maybe their young stars continue to improve and maybe Scott Brooks continues to coach them to an elite level. That doesn't mean that their "time will come" and they will soon win their inevitable championship.
That isn't to say that the championship ship has sailed, either (pun intended). But that isn't something the Thunder can concern themselves with. All that general manager Sam Presti should be thinking about is how he can improve his team this summer.
Because while the formula for building a champion doesn't necessarily involve some organic annual growth process, it almost always involves fielding a team that is really, really good.