The player at the back of the court passes the ball to a setter and lies down. The setter then overhand passes the ball high before setting the ball up for the other player, who has now returned to his feet, to approach and spike the ball.
This drill improves agility and helps shorten approach time.
New hitters rarely miss because of their arm. They miss because of their feet. Build a reliable approach, then time it with your setter.
When your hitter gets stuffed, five teammates standing and watching is how you lose the point. Good attack coverage turns a blocked ball into a second swing.
Coaches spend hours correcting arms in serve receive when the real fault is almost always the feet. Fix the movement and the platform fixes itself.