These are notes I have from class. These are the same notes that ever other game design student I've talked to has also received. I also feel as though these are the best qualifications for a video game:
Objective:
1) Goals and Objectives - The game must present a clear winning condition, and must offer subsequent tasks that must be completed in order to achieve the winning condition. Multiple objectives means there is more gameplay and challenge, and thus increases the play length. Objectives can sometimes be a natural part of the gameplay.
2) Rules - The player of a game must never be allowed to completely break the game by doing whatever they want. There must always be limitations which block the player from just finishing the game instantly. Rules may also add challenge naturally or may allow for clever players to exploit loopholes in the rules, and increase the fun the player has. Some rules may need to have exceptions as dictated by the gameplay scenarios.
3) Obstacles and Failure States - The main means of creating challenge is to introduce certain obstacles which the player has to overcome in order to proceed through the game. There are many forms, and the goal is to ensure there are multiple types of obstacles, so that the gameplay is always refreshing and never becomes boring. Failure Statues are the idea that the player's progress needs to be impeded in some form for failing the game in some way, including losing or dying. Punishment may be in more forms than just a simple game-over, such as implications for the story or removing player rewards. The idea is that player should feel encouraged to learn from their mistake and improve, and with practice from replaying eventually master the game.
4) Boundaries - There needs to be a defined play field for all players. Players must not be allowed to break out and exceed the limits of the game world. One may define that the entire universe is the play field, but this still counts as an acceptable limit.
5) Engagement - How the player actually engages with the game, and what kind of experience, feelings, emotions and lessons they take away from it after they finish playing. (The how is subjective, but a game MUST engage its audience on some level, otherwise it is a meaningless task)
Subjective:
1) Visual - How the game looks, or doesn't look.
2) Audio - How the game sounds, or doesn't sound.
3) Player Input - How the player actually interacts with the world.
4) World Output - How the world responds to the player and notifies the player back.
On the Objective scale, Depression Quest lacks #3 and #5 and #1 is never made clear.
Furthermore, I made a well received blog entry (that I've since moved to a new blog) which expands on this:
Video Games Are...Now please try and tell me how Depression Quest meets any of those criteria I have listed?
