Everyone has their favourite quotes. Maybe its a line from an emotionally-gripping scene in your favourite movie or that one joke from The Simpsons that could reduce you and your friends to giggling morons weeks after you first heard it. Perhaps its something you read at school that managed to cut through the tedium of rote learning and stick with you, or that one timey-wimey speech. Whatever the source, it probably doesnt take more than a moments thought for you to remember your favourites and why you like them so much. Trying to remember your favourite quotes from video games, though? Thats another matter. There are loads of memorable game quotations  the sort that you see plastered across T-shirts  stretching back to Our Princess is in another castle! and beyond, but we dont make reference to these lines because theyre brilliant writing. Instead, we use them as proof of our gaming credentials; you played Super Mario Bros and if someone recognises the quote, they know youre old-school. Otherwise, if a game gets quoted its usually to poke fun at it  mocking some mangled translation, cheesy dialogue or terrible voice acting. All of which begs the question: why, when modern video games have blockbuster budgets and professional actors as standard, do we still lack a shared culture of brilliant video game dialogue? Why are games as witty and quotable as Portal the exception rather than the rule? Most people assume its second-rate writing thats to blame, or that the game team didnt really care about the story. While its true that depressingly few game writers have prior experience, there are also a bunch of unique challenges in video game narrative that even veteran storytellers struggle to deal with: