"Who's the GOAT?" is a question that almost always involves a discussion on the number of rings each player has.

The last line of defense for Michael Jordan's faithful is often that he's 6-0 in NBA Finals series (and that's a pretty strong line of defense).

At the same time, when breaking down the league's all-time hierarchy, those on the other side of that coin are often dinged for having no rings.

All-time greats like Charles Barkley, Karl Malone and others don't have that feather in their caps, which makes arguing for their resumes over title-winning stars a little more difficult.

But instead of trying to stack those players up against the likes of Jordan, LeBron James or other champions, let's just focus on the group of players who never reached the league's mountaintop.

Who are the greatest players in NBA history to never win a championship?

The following top 10 is an answer to that question. But first, let's break down how it was answered.

Methodology and Close Calls

The criteria for this list is slightly less cumbersome than that of some of our other recent historical deep dives.

First, the field of available players was pulled from last summer's all-time top 50. All non-champions from that list or its honorable mention section were included (with the exception of active players, who still have time to win titles).

Then, the following were found for each player:

• Career box plus/minus: "...a basketball box score-based metric that estimates a basketball player's contribution to the team when that player is on the court."
• Career wins over replacement player: The cumulative variant of BPM (think points versus points per game).
• Playoff BPM and WORP.
• Career MVP Shares: "The formula is (award points) / (maximum number of award points). For example, in the 2002-03 MVP voting, Tim Duncan had 962 points out of a possible 1,190. His MVP award share is 962 / 1,190 = 0.81."
• Accolade Points: Three points for a first-team All-NBA selection, two points for a second-team All-NBA selection or a first-team All-Defense selection, and one point for a third-team All-NBA selection, a second-team All-Defense selection or an All-Star selection.
• A fan vote.

Once those numbers were in place, the players were sorted by the average of their ranks in each category. That yielded the top 10 that follows, but it also led to some difficult cuts.

Bob Lanier, Vince Carter, Grant Hill, Chris Webber and "Pistol" Pete Maravich were some of the players who missed out on top-10 status.

Also of note, though Elgin Baylor appeared in only nine games in 1971-72 and didn't log a single minute that postseason, he was given a championship ring by that Los Angeles Lakers squad. For that reason, you won't find Baylor on this list.

10. George Gervin

George Gervin is one of the greatest scorers in NBA history. Beyond his 26.2 career points per game, a mark that ranks ninth all time, Gervin had a dominant six-year stretch from 1976-77 to 1981-82.

In that stretch, he averaged a league-best 28.7 points per game. Kareem Abdul-Jabbar's 25.1 points per game ranked second, and the distance between those two marks was the same as the distance between second place and 15th place.

Gervin also secured four scoring titles in those years and eclipsed 30 points per game twice.

Perhaps most impressive, though, was the efficiency with which he scored. Gervin's 52.5 effective field-goal percentage over those six seasons was well over the league-average 48.1.

Watch highlights of a young Gervin now and you'll see plenty of examples of his patented, and seemingly unstoppable, finger roll. His drives to the rim were smooth. And his touch inside was as soft as anyone's in the league.

9. Dominique Wilkins

Another dominant scorer, Dominique Wilkins ranks 14th in league history in career points per game. And he had a 10-year stretch in which he averaged 28.0 points, 7.0 rebounds, 2.9 assists and 1.4 steals from 1984-85 to 1993-94.

His scoring repertoire was less about grace, though. Wilkins consistently went to the bucket with ferocity, earning the nickname "The Human Highlight Reel."

"We call him 'Space,'" Wilkins' teammate Eddie Johnson said in 1982. "Because on the court, he lives in outer space."

That's an apt description of Wilkins, who scored a great many of his points from above the rim. But there was more to him than simply being a dunker.

"...when Nique wanted to play defense, he could play defense," Former teammate Kevin Willis said. "Everybody didn't want to give him credit on that end, but Nique could play some defense for sure."

He was also a decent rebounder and playmaker for a wing. He possessed a solid mid-range game that forced defenders to play him close outside the paint, thus setting up his drives.

Yes, the dunking is always what he'll be best known for, but Wilkins was a great all-around player.

8. Reggie Miller

Reggie Miller was basketball-wise beyond his years.

Over the course of his career, the league-average three-point attempt rate (percentage of shot attempts that came from three) was 14.3. Miller's was 37.1.

And the only players in league history who match or exceed Miller's career marks for three-point attempt rate and free-throw rate are Chauncey Billups, Spencer Dinwiddie, Danilo Gallinari and James Harden.

Miller's willingness and ability to hit threes and draw fouls made him one of the most efficient scorers in the league. During his era, his 61.4 true shooting percentage was tied with Magic Johnson for first among players who averaged at least as many points as Miller (18.2).

But what really sets Miller apart is the fact that he was even better in the playoffs. His postseason box plus/minus and scoring average are both higher than his regular-season marks. And despite the increased intensity of playoff games, he still maintained a 60-plus true shooting percentage over those 144 games.

7. Patrick Ewing

Another one of the NBA's 1990s standard-bearers, Patrick Ewing was among the game's most dominant bigs for the bulk of his career.

Through his 10-year peak (1987-88 to 1996-97), Ewing had a 4.0 box plus/minus that trailed only David Robinson, Hakeem Olajuwon and Shaquille O'Neal among centers.

All three, of course, won multiple titles. But Ewing was often mentioned in the same breath as them during their playing days.

In 1990, Jack McCallum made the comparison in an article on Ewing's evolution as a player for Sports Illustrated:

"The power, the intimidation, the fearlessness are still there, but so are grace and finesse and economy of movement, terms previously associated with Houston's [Hakeem] Olajuwon, Ewing's yardstick through most of the '80s, and San Antonio rookie David Robinson, the only other NBA center currently mentioned in the same breath with Ewing and Olajuwon."

In that same 10-year stretch, Ewing made 10 All-Star teams and used his wide-ranging skill set to average 24.0 points, 10.6 rebounds and 2.8 blocks.

Like several others on this list, he had the misfortune of peaking around the same time as MJ's dynastic Chicago Bulls. Otherwise, there's a good chance he would not have been eligible for consideration here.

6. Steve Nash

The 2003-04 Dallas Mavericks, the 2004-05 Phoenix Suns, the 2009-10 Suns, the 2001-02 Mavericks and the 2006-07 Suns rank first, second, sixth, seventh and 11th, respectively, in relative offensive rating (a team's points per 100 possessions minus the league-average points per 100 possessions).

What do those five teams have in common?

Steve Nash was the starting point guard for each. And the '02 Mavs are the only team of the bunch that Nash didn't lead in offensive box plus/minus (Dirk Nowitzki's 5.4 led the way that season).

With or without a championship, Nash was one of the greatest floor generals in NBA history. 

The two-time MVP is ninth in NBA history in assists per game, third in assists, 23rd in threes, second in free-throw percentage, 11th in three-point percentage and 19th in offensive box plus/minus.

And over his eight years as the Suns' starting point guard from 2004-05 to 2011-12, the team scored 116.4 points per 100 possessions with Nash on the floor and 104.8 with him off.

That impact was thanks in large part to Nash's pass-first approach.

"What has he taught us?" Charles Barkley asked about Nash for Time Magazine. "It pays to be selfless. You can be content just to make the players around you better... People think that in order to be a great player, you have to lead the league in scoring. Forget that..."

5. Allen Iverson

Unlike Steve Nash, Allen Iverson never had an Amar'e Stoudemire or Dirk Nowitzki to help shoulder the offensive load. For much of his career, the burden was almost entirely AI's.

Over his first 10 seasons, all with the Philadelphia 76ers, Iverson averaged 28.0 points, 6.1 assists and 2.3 steals. He ranked first, 22nd and first in those three numbers during that run.

And his total points in that decade, 19,115, was more than second through seventh place on the Sixers' leaderboard combined.

Of course, the knock on Iverson has always been the inefficiency of his scoring. He had an above-average effective field-goal percentage in just one of his 14 seasons. And his 21.8 field-goal attempts per game rank fourth all time.

But again, that ball dominance was arguably born of necessity. And even when using such a high percentage of his teams' possessions, they undoubtedly benefitted from his presence.

Over the course of AI's career, his teams were plus-0.6 points per 100 possessions with him on the floor and minus-2.6 with him off.

4. Tracy McGrady

In 2002-03, Tracy McGrady led the NBA with a 10.5 box plus/minus that is also the 20th-best mark in NBA history for a single season.

During that campaign, McGrady was the scoring champ and averaged 32.1 points, 6.5 rebounds, 5.5 assists, 2.3 threes and 1.7 steals. The Orlando Magic were plus-3.2 points per 100 possessions with him on the floor and minus-9.8 with him off.

He did everything for Orlando that season, essentially operating as a 6'8" point guard and dragging the team to the postseason. He totaled 25.1 wins over replacement player in 2002-03 (value over replacement player times 2.7). The rest of the roster combined for 0.8.

But McGrady was far from a one-season pony. From 2000-01 to 2007-08, his 6.6 box plus/minus trailed only Kevin Garnett, LeBron James and Chris Paul.

For nearly a decade, the point forward who could score from all three levels was one of the game's very best players.

He doesn't have an MVP or championship to show for his on-court greatness, but McGrady was a dominant force for most of the 2000s.

3. John Stockton

If box plus/minus were the only arbiter of this list, John Stockton would have the top spot.

The only retired players in NBA history with higher box plus/minuses are Michael Jordan, Magic Johnson, David Robinson and Larry Bird. On the wins over replacement player leaderboard (the cumulative variant of box plus/minus), Stockton trails only LeBron James and MJ.

A whopping 19 years of steady floor generalship, top-tier efficiency, unrivaled passing and relentless ball-hawking carried Stockton to the top of those lists.

And as long as he was the Utah Jazz's starting 1, the team had similarly positive results.

Stockton became Utah's top point guard for the 1987-88 season. From that point till his retirement in 2003, the Jazz ranked:

• First in winning percentage
• First in simple rating system (point differential combined with strength of schedule)
• First in effective field-goal percentage
• Third in points per 100 possessions
• Fifth in points allowed per 100 possessions

Shorten up the sample a bit and you'll find some truly mind-blowing individual numbers from Stockton. From 1987-88 to 1996-97, he averaged 15.6 points, 12.8 assists and 2.6 steals while posting a 61.9 true shooting percentage.

Even among title winners, few players in NBA history possess a statistical resume that tops this one.

2. Karl Malone

Karl Malone was there for nearly all of John Stockton's run with the Jazz, finishing scores of assists from the Hall of Fame point guard and piling up an absurd number of points over his 19-season career.

By the time he finished his career, Malone was first all time in free throws made, second in minutes played and second in points scored.

He's currently eighth in career MVP shares, trailing only Michael Jordan, LeBron James, Kareem Abdul-Jabbar, Larry Bird, Magic Johnson, Bill Russell and Shaquille O'Neal.

And finally, his 17 seasons with 500-plus minutes and a 20-plus scoring average is tied for first all time with Abdul-Jabbar and James.

Simply put, Malone was one of the most prolific and durable scorers the game has ever seen.

He could score inside and was a perfect pick-and-roll complement for Stockton. Over the course of his career, he developed a long-two game that was something of a precursor to today's stretch bigs.

Malone was also an underrated playmaker, posting a career average of 3.6 assists and topping 4.0 assists per game in seven different seasons. And of course, he was a dominant rebounder, registering 10 seasons of at least 10 rebounds per game.

If longevity were weighted a bit more in the methodology, Malone would've finished first. As it stands, he just barely missed that distinction.

1. Charles Barkley

Charles Barkley may not love analytics, but the numbers sure love him.

He's the only player in this exercise who ranked no worse than third in each category employed.

His basic numbers are plenty impressive too. For 11 straight seasons from 1985-86 to 1995-96, his averages for scoring, rebounding and assists never dipped below 20, 10 and three. And those 11 20-10-3 seasons trail only Kareem Abdul-Jabbar's 12.

What might really set Barkley apart, though, was his scoring efficiency. Despite an abysmal career three-point percentage of 26.6, Barkley had a 114 adjusted true shooting percentage (14 percent better than the league average over his career). For context, Karl Malone's adjusted true shooting percentage was 109.

That number was largely a product of absurd finishing ability that defied Barkley's size. The 6'6" forward dominated the paint, which was often packed with players much taller than him. Even with the disadvantage, he led the league in two-point percentage for five straight seasons from 1986-87 to 1990-91.

Beyond the efficient scoring, Barkley was also a uniquely gifted rebounder. He has, by far, the best rebounding percentage of any sub-6'6" player in the three-point era. The Round Mound of Rebound moniker didn't come out of nowhere. He knew how to use his body to carve out space before grabbing a board. And in a pinch, he was athletic enough to outleap plenty of taller players.

He was never able to leverage his nearly unprecedented production into a championship, but basketball is a team sport. His individual merits speak for themselves.