After Shikamaru's team failed to bring back Sasuke, the Akatsuki members were shown for the first time and they waited for 3 years before resuming their mission. Why did they wait?
They didn't paused there mission and resumed it later but they continued it behind the curtains. They have to capture tailed beast by an order and Naruto falls in last number and then they needed preparation too for sealing beats and location ensuring etc. They also had non-trustable member to deal with and maybe some other background stuff behind the curtains.