#1. Underwhelming matches
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The matches Styles put up at the beginning of his title reign were definitely not underwhelming. His match against Lesnar at Survivor Series is regarded as one the Beast's best, he brought out the best of Jinder Mahal at Clash of Champions and the six pack challenge at Fastlane was definitely an entertaining bout. But, after that things went downhill fast.
I do not mean to say that the matches since Mania were bad, but something more was definitely expected from them. Nakamura vs Styles at Mania was a disappointment for the lack of a proper storyline, and after that, every match was simply lacklustre. As WWE decided to play safe too often, we got two draws. First, at the Greatest Royal Rumble and then at Backlash. Although they redeemed themselves at Money in The Bank, the storyline was far too much stretched out for the match to have any relevance.
After a one-time encounter against Rusev at Extreme Rules, which was far too predictable, WWE repeated the same mistakes against Samoa Joe. Their Summerslam match was turning out to be great, but the payoff was definitely not good. Joe repeatedly lost to Styles at Hell in a Cell, Super Showdown and Crown Jewel, thus effectively stopping all his momentum.
I am not saying that the matches were bad, but due to booking faults, the matches had no hype which no amount of in-ring excellence can cure.
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