#3 CM Punk's Pipebomb

No one can forget the infamous 'pipebomb' by CM Punk, even though the promo was preplanned, it was absolutely marvelous. With this promo, CM Punk broke the fourth wall and blurred the line between reality and kayfabe.
This promo generated a huge buzz in the pro wrestling community and it skyrocketed Punk's popularity. Punk mentioned various other wrestling promotions like NJPW and ROH in his shoot against the company which no WWE superstar had done before.
This promo made CM Punk the underdog and helped him become the representative of the disappointed fans. This also solidified his gimmick as 'The Voice Of The Voiceless'.
WWE cashed in on Punk's popularity and made him the WWE Champion. This promo further cemented Punk's legacy and changed the landscape of WWE forever.
#2 Extending Raw To 3 Hours

In 2012, WWE decided to extend Raw to 3 hours. The extra hour of the show provided WWE with much more revenue, but, it came at the cost of quality.
WWE managed to create good storylines that kept the fans invested in the product during the initial years, but, after that, they couldn't keep up with it. The third hour of Raw puts the creative team under more stress they have to come up with more storylines and rivalries.
The effect of this decision can be felt now, more than ever as WWE creative is constantly struggling to create engaging storylines and this has resulted in massive viewership decline, especially during the third hour of Raw.