A few years ago a mathematician friend explained to me that the game of tennis is enjoyable to watch only because of the scoring system.
If players swapped serve alternately, and the tally worked as in basketball, (Nadal now leads Murray by 127 points to 43; new balls please) it would be almost unwatchable. But because tennis breaks the score into watertight compartments, namely games and sets, it creates a structure wherein a losing player feels he is still in with a chance right to the end. That makes the narrative of the game far more enjoyable to fans and players. And because some rounds (break-points, set-points) are more critical than others tennis’s moments of high tension are interested as in a good opera or play, with quieter moments when spectators can relax.
Excerpt from: Rory Sutherland: The Wiki Man by Rory Sutherland