Game feel is particularly bound up with usability concerns because of the delicate interplay of learning, skill, and challenge. To cut to the chase, properly balancing and tuning a mechanic to feel good is one of the most difficult challenges a game designer will face. There will always be a learning curve for a new mechanic. Players will be frustrated at first. They understand this and tacitly agree to a certain amount of frustration on the promise that some enjoyable, engaging experience will result. Remember what it was like to learn to ride a bike or drive a car. When you finally got it, how did you feel? Was it worthwhile? The designer must make delineation, then, between what frustrations are the byproduct of the skill building process, and what is a usability concern. The problem lies primarily in the fact that players can learn any interface. The challenge is to create a mechanic worth learning. This is a moving target-the amount of "worth" will be a factor of how difficult it is to learn, of individual players, and of the other rewards provided for mastery. A very difficult mechanic may be worth learning if it's a game you play with your friends over and over again, or if there's an online leader board. Or it may be that you enjoy the theme and art of the game particularly, or the story which is doled out after the completion of challenges. Or you may just be the kind of player who enjoys mastering exceptionally challenging mechanics. I tend to fall into this category-! loved Gunvalkyrie, Ski Stunt Simulator, and Trials: Construction Yard (possibly the most difficult game ever to be worth playing.) Depending on your design
vision, extreme difficulty may be okay. As long as the reward for learning the skill seems commensurate to your intended player, you're all good.