Why do Setters jump before setting the volleyball?

Question

Every time when the Setter is just about to set the ball he jumps and then sets the ball.
What is the rationale behind jumping?

Answer 1

1. The setter is higher. That means that the way of the ball from the setter to the attacker is shorter
2. If the setter is frontrow he is able to score directly on second.
3. The setter has a wider range of the timing when he is setting the ball.
4. The receivers can put the ball for a perfect reception closer to the net

Answer 2

There are multiple good reasons:

• Allows more angles and directions when setting
• It helps the attacker to align himself better to the ball and the opponents field
• Surprises the opponent's mid-blocker due to less predictable play