This function is a smart combination of algorithms that will repair an asset automatically (vertex welding, face orientation, edge collapse...).
Distance Tolerance: Merge any vertices whose proximity is under the given tolerance (by default in meters).
Orient faces: Orient Normals of adjacent faces consistently (unification of all triangles orientation).
NOTE Saying that a face is correctly oriented can often be subjective, as it depends on the position of the viewer. The orientation of faces in the Repair Mesh algorithm aims at uniformizing the orientation on a continuous set of triangles, but it can't ensure that the final result will be correct for the user. Although it fixes everything on most volumetric shapes (such as CAD models), there are other algorithms to orient faces based on a point of view for other cases.