assuming that that a BH, the singularity more precisely, is a point mass, a point having neither length, widths or heights, that leaves only the time dimension. and even there, it could be even not showing any measurable movement. stuck in time. so to speak. but the connection to the OP is , that there is movement in the magnetic field of the BH perimeter, and action in the infalling matter, and the interference of the two could rise to density waves, where material congregates. In that they resemble stars. as hown in the linked image.