"Silent protagonists allow the player to create their own interpretation of a game character. By not being prompted by scripted character dialog, the nature of that character (and sometimes even his/her gender) and what they say is left up to the imagination of the player. The character is a blank slate, which can more easily and fully be inhabited by the player, immersing them as fully as possible into the game. In some cases, such as the Myst series, the player's avatar is given no name or defining characteristics at all, meaning that the player themselves is effectively the protagonist of the game. This is in contrast to games such as Duke Nukem 3D, where the protagonist frequently interjects comments into play, and leaves the player in little doubt as to the nature of that character, and with the impression that they are simply puppeteering a distinct and separate character, rather than inhabiting the adventure themselves.
This device is fairly close in principle to that of the "masking effect" mentioned in Scott McCloud's book Understanding Comics - while the masking effect makes things such as facial features and body types in comic book and animated characters as generic as possible in order to allow for easier identification with protagonists, removing the notion of "otherness" from them, the silent protagonist is generic enough so that the player (usually silent himself while playing) feels no clash of personality or opinions during the game, or at least minimizes such a shock."