#10. Brock Lesnar

It’s rare for WWE to truly go all in on pushing a talent. With the possible exception of someone like Hulk Hogan, it’s difficult to remember WWE pushing anyone so hard, so fast, so comprehensively as young Brock Lesnar. His rookie campaign on the main roster included beating Hogan clean, winning the King of the Ring tournament, beating The Rock for the WWE Championship at SummerSlam, winning the Royal Rumble, and winning the main event of WrestleMania over Kurt Angle.
Lesnar wound up wearying of pro wrestling and the WWE schedule, and ultimately decided to leave to try out for the NFL, en route to his career in MMA. That he would take so much from WWE, at the risk of weakening everyone around him, and then leave before WWE could fully cash in was borderline unforgivable.
In the end, though, Vince McMahon is a businessman. He could have held a grudge but instead recognized an opportunity as Lesnar’ prime in UFC wound down, to bring back a familiar face to WWE, trained to wrestle at a high level, and with the legitimacy of MMA success behind him. It was a shocker when WWE re-signed Lesnar, but he has by and large been a successful attraction for over six years to follow.