Understanding the plugin mechanism is important to achieve better result and closer to what you expect.

The voronoi diagram is fairly simple to understand. It found the nearest point to a center.

 

this is a result on a 2D plan

 

The lines represent the axis placed at equal distance from two point and perpendicular to the line traced by thoses points.

This is the same process in 3D.

The placement of particles in xplode is therefore crucial for cutting pieces. The more particles will be closer and numerous, the more parts will be small and in number.

If the particles are placed on a 2D plane, the cuts will still be done in 3D space but the pieces will then be composed of parallel ridges.