#4 Bobby Roode
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The former TNA Superstar Bobby Roode made waves when he debuted in NXT. The fans loved every bit of his "Glorious" persona. He consistently delivered excellent matches down in developmental, and was finally thrust onto the main roster.
Although Roode did well for a while, and was featured in a Fatal Four-Way match for the United States title at WrestleMania 34, he didn't do much of worth since then.
Roode was drafted to Monday Night Raw in the Superstar Shakeup and has been an afterthought ever since. He went on to team up with Chad Gable, another NXT recruit WWE messed up. The duo is currently having regular matches against Aleister Black-Ricochet and The Revival.
They might get a tag team title shot at WrestleMania in a multi-man tag team match, but this is way worse than what Roode deserves. His downfall on the main roster is an absolute travesty.
Also read: 10 Superstars who need to switch brands after WrestleMania 35