-Mistico coming into the WWE, when he was considered one of the biggest draws in Mexico history and completely flopping and not adjusting to the WWE.
-The Muhammed Hassan "terrorist" angle on Undertaker. Was a legit surreal and crazy moment, but the London Bombing in 05 happened the same time as the angle and the WWE had to get rid of the Muhammed Hassan character.

I always remembered hearing that he was supposed to win the Heavyweight title from Batista at Summerslam 05 in DC too.
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Goldberg deciding to punch the limo window and got hurt for 6 months during the peak of his career, than coming back as a heel, but WCW was already bottoming out.
-Jake Roberts leaving the WWF in 92 as a potential top guy going forward with Hogan soon to be out of the WWF for good, along with Macho Man winding down, and Warrior getting deavored for sticking Vince at Summerslam 92 because he didn't get Patterson's spot as a booker.
-Verne Gagne not giving Hulk Hogan the AWA belt in 1983 before he bounced to the WWF. Hogan as AWA champ, while still on ESPN being practically seen as the biggest star in wrestling going national, while Vince would have probably gone with Jimmy Snuka to be propelled as the top guy of the WWF, which wouldn't have worked like Hogan more than likely.
-Dixie Carter choosing Hogan/Bischoff over Paul Heyman to run TNA.
-Ken Kennedy saying he doesn't do steroids than getting caught soon after in 07.
-Dr. Death getting waxed by Bart Gunn in the Brawl For All. It was set up for Dr. Death to win it all after JR hyped him up for years, only for his boy to get KO'd by Bart Gunn. The word was that they wanted to build it up to a program with Steve Austin vs Dr. Death supposedly.