Best Idea WWE Ever Had?

We've had the worst idea they ever had thread but what about the best? They often get a lot of crap but rarely get recognized for their good ideas.

The first idea that comes to mind is the transition into the Attitude Era but the more that I thought about it, (while it was a magnificent time for wrestling) I remembered that the Attitude Era was filled with major fuck ups. There was the "Even my immediate family bought it" incredibly stupid twist, The Artist formerly known as Goldust, the finish at WM 16, the finish at WM 17, the repetitive dysfunctional family rivalry, the PMS storyline, and perhaps the worst of all Mae Young giving birth to a hand.

So in my book the best idea WWE ever had was the Wrestlemania concept that has proved to be their biggest money maker