The researchers investigated how a structure called the forearc affects subduction zones. They used computer models to simulate different forearc properties and found that the forearc plays a crucial role in stabilizing subduction. By changing the thickness and density of the forearc, they observed how it can prevent the overriding plate from sinking and lead to a double-sided subduction setting. This study shows that the forearc is essential for maintaining a stable subduction system.