Communication is one of the hardest things that humanity accomplishes on a daily basis, and more often than not, there is a bit of loss when you translate thought to words and back to thought in someone else's brain.
In game design, quite often you have to start somewhere, such as, "This game will be like Zelda: OoT but with biblical mythology and a modern setting."
Such shortcuts allow for fast absorption of the key data, and can allow for discussion of the actual game development to begin earlier and at a faster pace.
But even using the above heuristic shortcut, some data can be misinterpreted, or flat out misunderstood. For example, does the Zelda aspect mean dungeons, a main weapon and different sub weapons? Does it mean heart containers are found? What is biblical mythology? Is it the parts in the bible? Or is it the parts that people make up as they interpret it? And by modern... do you mean now, within the last 20 years, or 20 minutes into the future?
Yes there will be questions and clarifications, but it sure is a lot faster than detailing it all at first, and pictures already begin forming in people's minds as the question and answer goes on. Collective brainstorming occurs, and a game gets designed.
This can often be seen as a "sales pitch" of the game, but this type of thinking and communication clearly shows what you want to do, and how it will be different from the current offering available.
"This is a MegaMan game where you're a an unemployed teenager and have to train and get jobs."
"Its like Bionic Commando, except sci-fi, 3-D and the mechanized arm is your wife."
So to everyone who has to work with other people on cross disciplinary projects, the greater your breadth of knowledge, the easier it will be to communicate. So read a book you don't like, play a game that sucks and has a low metacritic score, and finally, experience life. Good luck, have fun.