The article discusses how different types of beaches and surf zones behave differently based on their natural state. The researchers studied beaches over a few years and found that the type of waves and sediment affect how mobile a beach is. Reflective beaches with calm waves and fine sand are less likely to change, while beaches with medium-sized grains and changing wave conditions are more likely to shift. They also found that certain environmental conditions can predict how a beach will behave. Overall, the study shows that beach state is closely linked to wave height, sediment speed, and wave period.