Standing in one place and shooting a static target has its benefits.  But, if you want to add some movement into your shooting, engage moving targets and train under pressure, action shooting will elevate you to the next level.  The purpose of action shooting is to push your skills so that you respond better in a defensive situation.  But, above all, you will engage with like minded people and build a priceless community of friends.  Check out the below video for an example of a USPSA stage.