Make the production of the goods is not effective because of the monopoly, there are no competitors, it's not interested in the efficiency in producing much. The economic use of resources, it's not worth the most.
The production is inefficient because there is no monopoly, competitors, so they rarely pay attention to the productivity issue. The use of economic resources is not the best value for money.
Make production ineffective because the monopolist has no competitors have not pay attention to production efficiency much The use of economic resources, so no value most.