When all else fails, you still have the word useless. Use this adjective when nothing is working and there is no hope of improvement.
Less means "without." So something that is useless has no use or value, at least at the present time. Long ago, many blacksmiths concluded it was useless to try to get by making horseshoes after the automobile caught on. Their tools and supplies? Useless, so they thought. They moved on to other careers. Some even bought Fords. Fast forward about a hundred years. Ask antiques dealers if is it useless to present artifacts for sale to history buffs.