What would Conor McGregor's legacy be if he walked away from the UFC?

Let's make one thing clear about Conor McGregor's potential retirement: There's a strong chance he'll be back shortly and McGregor, Dana White, and the Fertittas will laugh about this on a private island somewhere in a few months.

But what if McGregor has decided he's had enough? What if the confluence of mad money, big egos, and a fatal fight McGregor witnessed firsthand leads him to leave the UFC?

At 27 years old, in the prime of his career, what would it mean for McGregor's legacy if he walked away for good?

Related: Conor McGregor out of UFC 200 after dispute over press conference

First, let's look at the facts.

McGregor is one of only two men to hold the UFC featherweight championship, a title he won after knocking out Jose Aldo in 13 seconds - the same Jose Aldo who's widely regarded as the best ever at 145 pounds.

In 22 career fights, McGregor is 19-3 with a 7-1 record inside the Octagon. Even his lone UFC loss to Nate Diaz is viewed as a major win: He headlined a PPV that drew a reported 1.5 million buys and was handsomely rewarded with the first guaranteed seven-figure salary in company history.

Fighters have made the UFC Hall of Fame for less, so a customized plaque in the Zuffa offices is assured, but his standing in the eyes of fans and critics is by no means indisputable.

Fair or not, there's a belief that a fighter is not a "true" champion if they don't defend their belt. McGregor has been the featherweight champion for a little over four months and he's already being panned for taking a pair of fights with Diaz before a defense.

If he walked away without defending the belt once, it would justifiably damage his claim to be the greatest featherweight of all time. Despite how swiftly he dispatched of Aldo, McGregor simply hasn't had the sustained success to definitively take that No. 1 spot.

Whether you consider him the best or second-best featherweight, however, McGregor's status as one of the company's most proven moneymakers can't be discounted.

His aforementioned million-dollar fight contract theoretically opens the door for a raise in fighter pay. However, outside of his opponents' salaries, there hasn't been much trickle-down to the rest of the roster.

In fact, McGregor's reputation as a company man may hurt his fellow fighters in the long run. As aggressive as he's been at the negotiating table, he has also agreed to take any fight under any circumstances. That temerity has endeared him to fans, but you can bet his employers are even more thrilled by the positive effect on their bottom line.

McGregor has done an incredible job of marketing himself and proving the power of the individual fighter. But any improvements to fighter salary that happen in his wake are purely incidental.

Oddly, the most impactful part of McGregor's legacy could be what happens next.

Rumors have swirled around him possibly starting his own promotion, especially after the fighter registered the McGregor Sports and Entertainment brand last year. Outside of Ronda Rousey, few fighters have captured the mainstream imagination quite like him. If anyone could become a one-man MMA show, it's McGregor.

Another oft-discussed option is the WWE. Having achieved everything there is to achieve in MMA, McGregor could venture into the world of professional wrestling in search of new challenges. His brash, sometimes cartoonish tirades would fit right in among the squared circle's larger-than-life personalities, and his coach John Kavanagh already joked about a possible move.

Not to mention the new Twitter buddies McGregor followed shortly after his retirement announcement:

Looking at those options, it's disappointing to realize that the most likely outcome is still McGregor's return to the UFC - whether it's in six months or six days. There is simply too much money to be made by both parties for this situation not to work itself out.

And if that's how it goes, it will be hard to view McGregor as more than just another fighter; a great one, to be sure, but one whose peak and eventual decline will make him no different from many who have come before, shaken the money tree, and left only a marginal impact on the sport as a whole.

Then again, if McGregor brings 70,000-plus to Croke Park in Ireland next year for the first-ever McGregor Fighting Championship show, co-produced by Vince McMahon, it's the first half of his career that could become insignificant in comparison.