Actually it is about creating the character the best design or the best role play potential, depending on your goals. In a FPS, you just shoot. Also in many CRPGs there are puzzles and riddles that you have to think your way past. In a FPS, you just shoot. Another thing in CRPGs you can interact with the world in a more immersive way through not only interacting with others but also withthe environment. In a FPS, you just shoot.