#2 John Cena getting squashed
After ending The Undertaker's streak at Wrestlemania 30 in 2014, The Beast, Brock Lesnar returned on Raw to challenge, the poster boy of WWE, John Cena for a match at Summerslam for the World Heavyweight Championship.
And for all the hype and excitement surrounding the match what we got was a damp squib. Cena was beaten and victimised by Lesnar in a squash match. He received 16 German Suplexes and 2 F5s, in a completely one-sided beatdown. Given John Cena was still the face of the company, WWE, in order to make Lesnar look unstoppable, shockingly destroyed all the credibility of the 16 times World Champion.
Also, there was no other legit draw other than Cena back then, as The Shield was new, Punk had left WWE, thus, it caused a subsequent drop in the viewership and from the Summerslam of 2014 to till now, WWE has lost over 1.5 million viewers.