2016

Who won: Triple H
Who should have won: Dean Ambrose
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2016's edition didn't nearly reach the disaster levels that the previous two Rumbles had, but it was a whole big bag of mediocrity. The Authority storyline had grown beyond stale in the previous couple of years and it now combined with the ongoing Roman Reigns push to produce an entirely bland experience.
Bending over backwards to put as many obstacles in Roman Reigns' path as possible to get him over as an underdog, the match centered on a title defense. Roman Reigns would have to put his title on the line in the Rumble itself, with the winner emerging as champion. That winner would be the most uncreative choice possible, Triple H.
It was all just another boring slog to WrestleMania where Roman Reigns would regain his title in one of the worst main events in the history of the Showcase of the Immortals.
Dean Ambrose, meanwhile, had established himself as an organically over fan favorite since the breakup of The Shield. His "Lunatic Fringe" persona was then genuinely hot and a Rumble win would have worked wonders for him. If necessary, he could have gone into WrestleMania as the heel challenger to his former stablemate, which would have been more compelling than what we got. Instead, Dean Ambrose had a terrible match with Brock Lesnar that destroyed the momentum he'd built.
And WWE wonders why it has to rely on nostalgia acts...