#3. JBL - A change in gimmick led to WWE Championship success
JBL's WWE career was potentially in danger in 2003-04 after Farooq's character was written off and The APA was finished for good. It took a drastic change in character for him to save his WWE career, but few did it better than him.
As controversial as JBL is, his shift in character was perfectly timed, as Kurt Angle and The Big Show were injured, while Brock Lesnar left WWE. The company needed a top heel on SmackDown and JBL was the solution, as he became an instant-heat magnet.
It was around April-May when Eddie Guerrero was disappointed about "not drawing" enough as the WWE Champion. While it was hard to blame him, he took it personally and requested to drop the World Championship.
In June 2004 at The Great American Bash, JBL won his sole WWE Championship and held it until WrestleMania 21, where he helped establish John Cena as the new face of WWE.
There were a lot of factors that led to JBL's WWE Title reign, but the change in character was so perfectly executed that it was hard to deny him that spot. He would hold the record as the longest-reigning WWE Champion in SmackDown history until AJ Styles surpassed him in 2018.