Proper use volume control?

1) To move the soundstage forward or back to where it should be or where you like it.

2) To get fuller details from PPP to all the way to FFF.

3) To get the room playing as loud as you imagine/remember in a concert hall/stadium setting.

4) To "fill the room" without creating unwanted wall and other reverberations/resounances.

5) Any other reasons.