In nature, liquid transport often relies on soft structures, such as valves, cilia, or porous walls, that deform under flow to passively regulate circulation. These structures have inspired the design of microfluidic devices and soft-robotic systems. However, sometimes these soft structures fail. For instance, soft valves are meant to close gently to prevent backflow, but under certain conditions, they can instead undergo snap-through instabilities: instead of sealing properly, the leaflet suddenly bends in an unintended direction. Such failures disrupt normal flow and can lead to pathological conditions. In this internship, we will explore these mechanisms using a simplified, upscaled experimental model of a soft valve in a flow at low Reynolds numbers.