How can you design game mechanics that are engaging and not frustrating?

Players need to feel some level of challenge to overcome, with a reward for overcoming it which generates a sense of accomplishment and empowerment. Depending on the game, if you don't offer enough challenge at the right time the game could feel too easy and you lose tension in the gameplay. If the obstacles feel too challenging such that they seem impossible to overcome that can lead to frustration and players giving up a no-win scenario. If they can feel that their losses are fair and that they are close to overcoming them, they will feel encouraged to continue. The right reward can reinforce the challenge being overcome with something to work towards and eventually celebrate once attaining.

Based on the game you're making you need to make sure that the action the player is performing matches with what they see on screen. If the mechanics don't function correctly, that can overall lead to a bad experience and negative feedback. likewise, If the reward that follows does not match (for example, killing an enemy and picking up health from them) the work put into completing that action then subconsciously the player may not find it enjoyable. This balance changes based on the type of game you're making so take time to iron everything out.

There are games that at times can rob a player of agency, like situations where it doesnt matter what they did previously, they're railroaded towards a predetermined game event. (for example making the player choose between two options but no matter which they pick, the outcome is the same). This can feel initially like its making the game more interesting but consider how it can make the player feel like their choices and actions don't matter - that they have no power. they'll get frustrated by these choices eventually and become detached. immersion will go out the window in these cases. it can even lead to resentment and a feeling of futile unfairness.

If I asked you to make a game about a ball, most people may do just that. However, what if I told you to make it interesting? What mechanics would you add? Maybe you would make the ball bounce or roll down a hill. Or, you could give the ball a name, a face and a backstory. Or perhaps the ball could mutate and take the form of other objects. Would be a pretty cool little game right? Now imagine you take all of that away and you have a ball that doesn't bounce or doesn't roll. Probably wouldn't feel too immersive right? As you design make sure that you're engaging your player by considering player agency (making a ball bounce instead of standing still for example) and how that feedback will affect the players experience.

Every game is different which means that player progression will be different as well. Adding variety will keep things fresh and avoid stagnation, whereas progression is a great indicator as to where the player has gone so far. Monopoly, as an example, is game where players buy land properties in order to build up their empire. There are a lot to choose from and players can see which properties they have as the game moves forward, thus offering a engaging amount of Variety and progression. The game even goes further as to make you vulnerable to losing your properties, i.e losing your progression, adding yet another layer of depth to the game. Think about these things when you build your game and how you can make these two concepts unique.

Fail fast, fail often. You may have the best idea ever, the best mechanic even, but if the game isn't fun or if your mechanic doesn't work then you're out of luck. This is why testing and iteration is important. You can never improve a product without putting it through tests. It would be like selling a car that hasn't been tested for safety and inspection. How do you know if the car wont break down, or the engine wouldn't blow up? You couldn't unless the car was tested and given a stamp of approval.

Essentially, If you have an action, that leads to something happening on screen, make sure that action lines up with the feedback the game is giving to the player. Unless this is intentional, whoever is playing the game will ultimately not enjoy the experience. Test regularly, find these discrepancies and work to make a better game for your audience to enjoy!