protected void checkMaintenance() {
    //  TODO:  In principle, this should be extensible to Vehicles as well.
    if (! (basis instanceof Venue)) return ;
    final World world = ((Venue) basis).world() ;
    if (world == null) return ;
    final boolean needs = (state != STATE_RAZED) && (
      (state == STATE_SALVAGE) || (! goodCondition()) ||
      needsUpgrade() || burning
    ) ;
    if (verbose) I.sayAbout(basis, "Needs maintenance: "+needs) ;
    world.presences.togglePresence(
      basis, world.tileAt(basis), needs, "damaged"
    ) ;
  }