We want to allow the player to save his/her game progression and continue playing the game in some other days. Some games allow the player to save the game anytime, but some require the player to reach the save point in order to do so. For the first option, you'll need to save a lot more data, especially if the game is action-heavy and not turn-based; otherwise, problems may occur. This is because an action-heavy genre, such as action RPG and FPS, has so many events happening at the same time that if you don't save the current states of all the AIs, events, movements, physics, and so on, the game will not be correctly restored when the player tries to load back the saved game next time.

With the save point, problems like this can be avoided because the game designer will make sure that the save point is being placed at a place where player is certainly safe and no important game event is going on in that area at that time; therefore, less data is needed to be saved.

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