These sandals push your feet forward because the back strap does not extend back far enough. This is why they feel like they fit small. As you walk you realize your toes are almost hanging off the front. Consequently, they walk like flip flops dragging and slapping at the heals. If you tighten the cross straps enough to keep your feet from working their way forward, your toes get squeezed and it's very hard to snap and unsnap the clip.