Before the health insurances era Doctors were often payed in nature with eggs, chicken or other farm products. Needless to say that they were often poorly paid, furthermore people called them so lately that the care was unable to keep them alive and the doctors lost their patients in the same time. Once the Doctors and the people they cared got the health insurances to be created Doctors received currencies for their services and could see more than once their patients. The issue of payment was transferred to the insurer. In the beginning insurers reimbursed with a fee for service model like the patients did previously. But the increasing amount of money needed made them think of an alternative payment model. And here came the Pay for Performance model.
France has already put in place such a payment model here:
USA will implement this mode of payment in 2019 here:
Developing countries have already experienced these kind of payment here:
Below are other links related to the way Doctors will be payed in the future: