Sand washing away from under my feet

I stood in the sea and let the waves wash over my feet. As the wave went out I could feel the sand being pulled away from under my feet.

It didn't seem to be washed away anywhere else. I can't find a clear description of this online. I was wondering whether it is linked to dilatancy (see https://www.scientificamerican.com/article/make-water-disappear-with-the-wet-sand-effect/) This is the effect whereby sand around your feet appears drier than the rest of the sand because the pressure causes the sand grains to spread apart. The water then flows into these wider spaces. If the tide puts even more water in, might that make the sand flow more easily by making it more like a liquid?