Why is Mahjong played counter-clockwise?

Why is Mahjong played counter-clockwise? Drawing tiles East starts the game by discarding a tile faces up in the center of the table. South then draws & discards a tile, followed by West and North. Thus, the draw goes counter-clockwise around the table, unless a tile is thrown which a player can claim.

Drawing tiles

East starts the game by discarding a tile faces up in the center of the table. South then draws & discards a tile, followed by West and North. Thus, the draw goes counter-clockwise around the table, unless a tile is thrown which a player can claim.