Set Pivot (Vertices)

Use the Set Pivot action to move the pivot point of this Mesh to the average center of the selected vertices.

Tip: You can also launch this action with the Ctrl/Cmd+J shortcut, or from the ProBuilder menu (Tools > ProBuilder > Geometry > Set Pivot).

Centering the pivot on selected Vertex points

In this example:

Left panel: The pivot point of the log is at the end corner of the cylinder.
Middle panel: The vertices on the end are selected, so the Set Pivot action changes the pivot to the center of those end vertices.
Right panel: The pivot point is now in the center of the cylinder end, even when in Object editing mode.