#6 Shinsuke Nakamura was used terribly

Shinsuke Nakamura is widely regarded as one of the best in-ring performers on the planet. He was a megastar in Japan, a megastar in NXT, and a, well, “Rock Star” in WWE who has been booked terribly since his main-roster debut.
Ever since being called up to SmackDown Live in April, fans have complained about how “The King of Strong Style” has been handled compared to his days in NXT, where he was one of the brand’s most popular Superstars.
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His rivalries with Dolph Ziggler, Baron Corbin and Jinder Mahal were underwhelming, while his wins over John Cena, Randy Orton and Kevin Owens could have been ‘statement victories’ on pay-per-views but occurred in one-off matches on SmackDown Live instead.
After a disappointing year, 2018 is almost guaranteed to be better than 2017 for Nakamura, especially if it begins with a feud with AJ Styles over the WWE Championship.