Objective and feedback

Always remember the player objective when designing--the goal to be reached by the player during gameplay; this may be reaching a specific location, defeating a specific enemy, achieving a financial target, or something else. Most players like to feel successful, like they're moving toward that goal. During gameplay, they'll typically look for both overt signs of progress (such as mission complete popups and victory sound effects) as well as convert signs of progress, such as meeting a friendly unit that offers to help you reach a location, open a hitherto locked door, find the murder weapon in a mystery game, or catch sight of the destination from a high vantage point (such as a watch tower), among others. It's important to reach a balance between these two types of signs or feedback, and to steadily provide them in the level through props, characters, dialog, architecture, special effects, and anything else you can put into a level. If the level features little feedback, the player loses interest, and feels defeated or bored. If the level features too much feedback, the player feels frustrated and overwhelmed.