Effects of referees in the volleyball are the least in comparing all other contact sports, football, basketball, etc.
If you are Ronaldo, you can touch any other player - but, if you are touched, it is immediately called faul. Hate football, succcer
If you are Lebron James, you can touch any, but, if you are touched, it is immediately called faul. Hate basketball, bastardsball
If you are a rich club or if you are a club with lobbies in these sports, manipulating the results are very easy using referees. Hate lobies.
No more succers, bastardsballs, etc. These are disgusting sport industries.
In volleyball, such things are minimum as it is not a contact sport.
This is why volleyball is the best in team sports.