Under lease and affermage contracts, the private partner's profits depend on the utility's sales and costs. The key advantage of this option is that it provides incentives for the operator to achieve higher levels of efficiency and higher sales. The principal drawback is the risk of management reducing the level of maintenance on long-lived assets, particularly in the later years of the contract, in order to increase profits. Further, the private partner provides a fee to cover the cost of using the assets although the private partner does not provide investment capital.