Though the Yes! chant is clearly manufactured and designed for crowd interaction, there have been several moments along the chant's journey where it has organically grown beyond belief.
One of those moments was the 2014 Royal Rumble.
By this time, Bryan was in the midst of a feud with The Authority, who were screwing him at every turning. Bryan actually opened the show that night, fighting against Bray Wyatt, but given he was so popular, fans were expecting him to pull double duty and win the Rumble match itself.
Not only did that not happen, but Bryan failed to even appear in the match. It was a moment that forced fans to turn on the company even more, showering the final moments the match with chants for Bryan: as well as repeated calls of Yes!
Those calls only intensified when it became clear Batista was going to be winning the Rumble match, and setting up a main event with Randy Orton at WrestleMania. Of course, as everyone knows, Bryan managed to muscle his way into that match and steal the entire show.
When Rey Mysterio entered the match last, he was showered with boos he probably didn't deserve. But this was supposed to Bryan's night in the eyes of the fans, and when it became clear he wouldn't be closing the show, the Yes! chant went to the next level in terms of popularity as almost everyone sided with the sport's unlikely hero.