How does the two-bounce rule function on service and return?

USA Pickleball Rule 4.B, commonly called the 'Two-Bounce Rule' or 'Double-Bounce Rule', mandates that the ball must bounce exactly once per side following the serve before any player can strike the ball out of the air. The receiving team cannot poach or volley the serve directly from the air; they must let it bounce in the service box. Similarly, when the return of serve lands on the server's side, the serving team cannot volley it out of the air; it must bounce once. Once these two initial bounces have occurred, both teams enter open volley phase and may hit balls out of the air (subject to kitchen restrictions) or off the bounce.