Delivery of quality services that provide value for money with sound finances encourages a long-term approach to the creation and management of public sector assets. Achieving value for money in the provision of a service requires that full account is taken on the risks and costs over a long timescale as opposed to focusing on short-term capital expenditure. This requires a two-sided model of financing the project, one that is reactive (short-term) to the needs of initial equity investments, and another that is proactive (long-run) in financing sustainability. The latter is related to ensuring quality. Quality services can be sustained over many years at the lowest long-run economic cost.
The key is to specify the output of service required to allow the private party to determine the inputs required and to "sketch" their cost curve over the long run. This involves no only infrastructure but other subjective attributes linked to collective performance and management. The private party must no contain a great deal of control over the standards to prevent from conflict of interests in evaluating quality of services.