A golfer is disqualified if they do not sign their scorecard

In professional golf, a player is automatically disqualified if they do not sign their score card after the round. There are a few reasons for this harsh-seeming rule. One is that a signing signifies that the player acknowledges the game they played and the professionalism needed in it. The second is that the player needs to make the scorecard official, so if there are any discrepancies or issues later on, the judges can look to the scorecard for the official ruling.