Why Brock Lesnar vs The Rock has not happened this year?

The Rock vs. Brock Lesnar is being much discussed, either this year or SummerSlam WrestleMania 30 in 2014.

The main reason that has not happened this year is because the authorities wanted to The Rock in a story with the WWE Title.

With the schedule and everything else Lesnar, WWE would not have considered that much sense.