Professional wrestling Legend and a future WWE Hall of Famer Jim Ross who is currently working as live match commentators in the All Elite Wrestling recently talked about the original Brand Split of the WWE and he revealed why he loved the concept of it.
The first and original brand split took place back in 2002. When WWE bought WCW, they had the plan of running WCW as a parallel show, even they were attempting to do it after buying WCW by introducing a WWE vs. Alliance storyline where the alliance was WCW and ECW.

Jim Ross Reveals Why He Loves The Original Brand Split
The whole year of 2001 was spent in this storyline. The idea was excellent but the execution was not. The plan of running WCW as a parallel brand to WWE failed drastically and after the Alliance lost to team WWE at Survivor Series, WCW could never get their own show.
But the plan of running two shows parallel was not been washed off by WWE. instead they came out with a better plan. They decided to run RAW and Smackdown as two separate brands for the first time in WWE history.
Since the existence of Smackdown in 1999, it had been the B show of WWE. For the first time in WWE history it was being treated as an equal show to Monday Night RAW. In 2002 WWE came out with the unique idea brand split and they decided to make two different rosters out of all the wrestlers they had.

The storyline owner of Monday night RAW was Ric Flair and Smackdown was owned by Vince McMahon. The first ever draft pick was the Rock to SmackDown. After WWE came out with this concept, they got more chance of building more stars in a better way. In 2004 WWE return with the draft for the first time Since 2002, and to be honest that draft was way more fun than it is now. The most ever brand split change the course of the WWE forever.
Jim Ross who is currently working as live match commentators in the All Elite Wrestling recently spoke on his Grilling JR Podcast where he talked about the original Brand Split of the WWE and he revealed why he loved the concept of it. He said;

“I loved the game plan. I liked the brand split a lot except when we started intermingling and the exclusivity became a misnomer. To me, the exclusivity was the selling point of having two brands. If you like Stone Cold, well you better watch on Monday.
“If you like The Rock, then you better watch on Thursday or Friday or whatever day it’s going to be. I liked that. I also liked the fact that keeping them separate and not contaminating them with each other would allow you to have your big Super Bowl.
“They got WrestleMania. I’m just giving you another main event that you can make millions of dollars on. It’s the Super Bowl of Sports Entertainment. That never really happened because the intermingling started right away and all this other sh*t that diluted it and it became a failure.”
H/T to WrestlingNews.co for the transcription