You can set Pathfinder Options from the Pathfinder panel menu or by double-clicking a Pathfinder effect in the Appearance panel.

Precision

Affects how precisely the Pathfinder filters calculate an object’s path. The more precise the calculation, the more accurate the drawing and the more time is required to generate the resulting path.

Remove Redundant Points

Removes unnecessary points as you click a Pathfinder button.

Divide And Outline Will Remove Unpainted Artwork

Deletes any unfilled objects in the selected artwork as you click the Divide or Outline button.