4. Bret Hart was a kind of wrestler the WWE no longer needed.
Bret Hart was very much a traditional wrestler, one who played by the old school rules and saw little reason to change.
However, the WWE in the late 1990s had become a fertile breeding ground for a new kind of wrestler; the anti-hero. Men like Stone Cold Steve Austin and The Rock proved that generic, white bread babyface heroes or black hat wearing villains were no longer a viable option.
In fact, Vince even went on the screen to say as much;
In this new "Attitude Era" earnest wrestlers like Hart were an anachronism, a relic of the past. However, WCW was still more of a 'wrestling' company than an entertainment company as WWE was trying to become, and Hart would find fertile ground for his type of wrestling character with McMahon's rival promotion, an arrangement that benefited all involved.