Reporters obtained the following quote from the background information supplied by the inventors: “ Technical Field “The present disclosure relates to a motion analysis device, a motion analysis m ethod, a motion analysis program, and a motion analysis system. “Description of the Related Art “At training sites for various sports or at production sites such as factories, the capability of a player or the skill of a worker may be assessed by analyzing the motion of the player or the worker. For example, Patent Literature 1 descri bes an assessment system that objectively assesses the motion of a player who is taking exercise. “The assessment system identifies the play or performance of the player to be as sessed based on motion data indicating a series of motions of the player through classification machine learning, and assesses the degree of attainment in the i dentified play or performance through regression machine learning. This allows the player and an instructor to identify the degree of attainment in the play or performance of the player.