Liner creep happens when a liner fails to retain its shape and elasticity. It's a common problem in unreinforced liner materials like EPDM or PVC. Even though they're much thicker than RPE, they gradually stretch out from the downward pull of gravity and water weight.
Liner creep creates immense stress on your anchor trenches and can cause your expensive stone edging to shift or collapse. A stressed liner is also much more likely to developed leaks. RPE's internal reinforcing scrim prevents it from stretching so it never loses its shape or strength.
