How can a Grav site disappear without trace?

A couple of hours ago I was looking at a file in cPanel at our hosting service when the whole site (grav-website folder) disappeared without trace.

Of course I do not suggest Grav destroyed itself but does anyone know such an event could happen?

Fortunately we have a recent backup copy.

It turned out the files in our site directory (public_html/grav-website) overwrote the files in a backup (public_html/grav-website-100817/grav-website).

Hard to see how one could do that by accident in cPanel as there is no drag and drop, and confirmation of a move is required. Maybe the sub-directory names were a factor.

Moral. Keep backing up.