Games spend enormous amounts of time establishing who the player character is. There are biographies, costumes, cinematic introductions, tragic childhoods, complicated family trees, heroic musical themes, and enough lore to explain why somebody has worn one particular shoulder pad for the last three hundred years. All of that can help define a character, but it can't make the player feel like that character. A detective doesn't become believable because they wear a trench coat. A survivor doesn't become vulnerable because their clothes are dirty...
