Why is the position being moved after transforming the point cloud into the Mesh

Hi, i am using this structure to generate solid meshes from a LAS, extruding the point from x,y and z and then building the mesh of each small cube.

But I found that the solid mesh was moved in the space (there is an offset) when I use cloud compare to viz it, and I don't know why it is occurred.

Very grateful for the answer!!

thanks:) !