10 Things You Didn't Know About Roman Reigns
2. He Has A Lot In Common With Tetsuya Naito

It's a shocking testament to WWE's stubbornness that Roman Reigns hasn't turned heel yet. Not only has the company wasted nearly two years trying to make the three-time WWE Champion universally beloved, but there's a pretty clear template for how well it might go if he were to turn.
Tetsuya Naito was a popular up-and-coming star in New Japan Pro Wrestling, but he simply wasn't as popular (or as talented) as the company's ace, Hiroshi Tanahashi. He went out with a knee injury at the end of 2012 and came back just in time for the G1 Climax tournament in 2013. The time off hampered his momentum, but the company still put him over in the tournament. After that, the backlash started.
Naito's win made him the top contender to IWGP Champion Kazuchika Okada, but the fans rejected the main event. At Wrestle Kingdom 8, a Tanahashi-Shinsuke Nakamura match for the IWGP Intercontinental Title headlined because fans voted it over the title match in a poll. Naito lost and continued to have trouble gaining fan support.
Finally, in 2015, the company turned Naito. Since then, he's been an incredible heel, forming and leading Los Ingobernables de Japon. He finally captured the IWGP Title, and everybody loved it. All it took was a character tweak to finally get Naito over, and WWE could do the same with Reigns.