When cellos and contrabasses seat on the left, they have a little advantage in turning over the music sheets.
Any section seating around center has the advantage in ensemble, especially horns and percussions.
When horns seat on the left or around center, their sound delay is usually much improved. The sound itself also becomes clearer. If the trombones seat apart from them, the ensemble is liable to be difficult, while it is easier to distinguish which is which. It is difficult to determine whether horns should seat in square or in line.