If all we ever do in training is work on the stuff that happens all the time, will our players be able to handle unusual situations?
Even high level players don't necessarily understand how little impact "quickness" training actually improves reactions.
Do you mix your practice session designs up a lot? Or are you the type of coach who basically does the same thing all the time?
There is a tendency to think that only 6v6 play can truly be game-like. This is a failure of imagination, though, and probably also a failure of focus.
There are a number of volleyball exercises where players start off blind to the ball, then have to find it. Here are my thoughts on their value.