A mental model is a preconceived perception of how something is expected to be, look, act or perform. The goal of the UX designer is to align the user’s mental model (how a user thinks it works) to the implementation model (how it actually works). People encounter frustration and make mistakes when interacting with a product, service, or experience because their mental model is different or conflicts with the designer’s implementation model. People form individual mental models based on their unique personal experiences and the world around them.