One Piece has long revolved around Luffy's promise to Shanks that he will return the Straw Hat once he becomes the King of the Pirates. Now that Luffy has defeated Kaido and risen to the rank of Emperor, some may think that time is near.But recent developments may suggest that both Luffy and Shanks may not meet, or fans may not get to see how it unfolds as expected. Their meeting may not happen when fans expect, it may be modified, or it may never occur. This one promise may not only change Luffy's relationship with Shanks but also alter the fate of the Straw Hat Pirates forever.Disclaimer: The article reflects the writer's opinion and includes spoilers from the One Piece manga.Why Luffy might never return the Straw Hat to Shanks in One Piece, explainedLuffy's promise to Shanks has always felt like the emotional endgame of One Piece. However, now that the story is in the final saga, there are indications that this will not play out as fans expect. Luffy has defeated Kaido and become an Emperor, meaning he has achieved "great pirate" status as Shanks once envisioned.Even Shanks' crew recognized Luffy's growth, yet Shanks seemed to actively avoid meeting Luffy and instead took the opportunity to address Bartolomeo for provoking him. This implies Shanks now views Luffy as an independent force and that Luffy's name stands on its own merit.In Elbaph, those implications get even stronger. Luffy now stands as Shanks’ equal, even earning the admiration of Colon, who once idolized Shanks. However, equality was never part of Luffy's goal- he swore as a child to have a better crew, a better ship, and the greatest treasure, to become Pirate King, and to exceed Shanks.Luffy and Shanks as seen in anime (Image via Toei Animation)Shanks even acknowledged this ambition when he said to Luffy good-naturedly, "So, you think you'll be better than us, huh?" That is the whole heart of the promise: the Straw Hat will only come back when Luffy is better than Shanks and not just equal to him.Prophecy adds another layer. Madame Shyarly prophesied that a man in a Straw Hat would bring down Fish-Man Island, probably connected to the Red Line's downfall and Joy Boy's age-old vow. Imu's obsession with the enormous Straw Hat also alludes to its deeper historical context, perhaps with a connection to Joy Boy himself. Being the keeper of that legacy, Luffy will have to hold on to his Straw Hat until he serves his purpose in this prophecy.Luffy and Shanks as seen in anime (Image via Toei Animation)There's also the symbolic core of the crew. The Straw Hat Pirates can't survive without the Straw Hat. To part with it before the end would equate to dissolving the crew and concluding their quest. The promise, therefore, can only be realized after Luffy is Pirate King.If Shanks survives to that day, the return can be their last, emotional encounter. Otherwise, Luffy can place it on Shanks' tombstone. Either way, the moment will come during the conclusion of One Piece, and the promise will be fulfilled in a way that reimagines both Luffy's fate and the Straw Hats' legacy.Final thoughtsLuffy's promise to return the Straw Hat to Shanks once he becomes a great pirate likely won't go the way that fans are projecting. He has beaten Kaido and has now become an Emperor, but Shanks still hasn't met him, indicating that their reunion may not be happening anytime soon.The aspects of prophecy, Joy Boy's legacy, and Luffy's literal role of the hat indicate that he must keep the hat until his journey's end.Related links:One Piece reveals Shakky's role in God Valley Incident, but it's not what it appearsCross Guild’s next big move could turn them into the modern-day Rocks Pirates in One PieceOne Piece’s endgame might secretly depend on Blackbeard’s fate