Animate the deformation mesh so that it passes over the object. If the Outside button is disabled, the deformation is only applied to the parts of the object within the mesh. To achieve this effect, you must move the mesh over the object. You cannot move the object through the mesh because the object axis parents the mesh axis.
You can also use the channel editor to animate individual or multiple points for the deformation mesh. See Animation.
To pass a deformation mesh over an object: