#1 Leaving developmental and threating to quit unless he was sent to the main roster
As you will see after this story, WWE giving Brock Lesnar preferential treatment isn't a new thing. Even during his days in OVW, WWE knew what kind of precocious talent they had on their hands.
While still in Ohio Valley Wrestling, Brock Lesnar told WWE that he would quit unless he was sent to the main roster. This is something that's unheard of in WWE and at this point, Lesnar had around one year of experience in professional wrestling.
The incident was described by Gerald Briscoe years later and here's what he said:
"One day I get a call, and it’s Brock. He’s really frustrated. He wanted to leave. Brock said, ‘I’ve got other options."
Most other wrestlers in developmental would get fired for offenses like this but Brock was rewarded with a move to the main roster where he won the WWE Championship six months after his debut.