Complex sentence: The game uses an "Edge Guard" to prevent the player from falling off certain platforms, because the developer believed this detracted from the experience by forcing players to pay closer attention to the character's legs than the world.
Split into simpler sentences: The game uses an "Edge Guard" to prevent the player from falling off certain platforms. This was because the developer believed that being able to fall off detracted from the game experience by forcing players to pay closer attention to the character's legs than to the world.