The Queen, Rook and Bishop are more valuable on open lines or half-open lines than on closed lines.
Open lines are ranks, files, and diagonals that are not obstructed by any Pawns.
A half-open line is a line on which only one player has no pawns.
In the diagram, the e-file, with rings on it, is half-open. The White Rook on e1 can reach any square between e2 and e7 in one move.
Whereas the White Rook on e1 is very active (i.e. controls a lot of squares), the other White Rook, on d1, is inactive, because the White Pawn on d2 blocks it.
The same things can be said of the Black Rooks as have been said about the White Rooks.
Conclusion: it is good to GET YOUR BISHOPS, ROOKS & QUEEN CONTROLLING OPEN OR HALF OPEN LINES.