It turns out that the finisher was created as a joke to make Undertaker laugh. He recalled how himself, The Rock, Steve Austin, The Undertaker, Mick Foley, and Kane would be working six-man tag team matches back in The Attitude Era.
At many shows, while working these matches, all of the wrestlers were trying to make The Undertaker break character by doing silly spots in the ring.
At the time and for the majority of his legendary career in the pro wrestling business, Taker took his character seriously and wouldn’t be out of character often in the public.
“I believe the first time Rock did The People’s Elbow was in a match where we were tryna make ‘Taker crack. It absolutely started [as a joke] and then it was getting huge reaction and everybody went with it.”
Once the move started to get over with fans, The Rock took it and started to use it more often and it eventually grew from there.
You can watch the entire interview by clicking on the player below: