The audio in jump-n-run, maze, or platform games is often just beeps, bangs, and boings. Shooters, action, and stealth games, however, have higher standards as far as immersion is concerned. They are typically set in realistic environments such as cities, space stations, castles, or wilderness.
Just like humans recognize an object's material by the way it reflects light, we intuitively gain information about our environment by how sound propagates. In real life, you can tell from afar whether footsteps stem from the narrow echoing hallway, or from the muffled carpeted room next to it. When one player patrols inside a warehouse, and the other sneaks around outdoors, their footsteps should sound different.
Games also often play the same sounds repeatedly: you hear your avatar's footsteps while exploring the haunted castle, the bangs of weapons discharging, or the avatar's gasp when he jumps from a ledge—over and over. Make sure to introduce some variation to avoid boring your...