The board is placed between the players so that the long diagonal starts at each player's left-hand side; the first square at each player's left hand is then a dark square (2.4); If the board is found to be wrongly positioned during a game, the game is annulled and has to restart (5.1)
Why people argue about this
People often assume that the board placement is purely a matter of preference, forgetting that it's crucial for maintaining the game's integrity according to official rules. The confusion arises because the exact positioning ensures symmetrical play and adheres strictly to the prescribed starting conditions outlined in 2.4, which could lead to disputes if not correctly set up.