The wall at the bottom of the point cloud is reflected into the scanner through the reflective surface in the middle and registered incorrectly at the top of the point cloud since the scanner cannot distinguish between in-line and reflected data.

This creates a problem during the registration process if there is a room on the other side of the wall where the reflection is shown, as the algorithms will try to match the actual scan data from that room with the reflection from the other room.

This can be cleaned up by manually removing the reflected points and merging a second pointcloud of the other room into the first scan after cleaning it up.