This puts the insurance organization at an immediate disadvantage, as the ability to pay out for all care needed is decreased when the risk pool is smaller.  In addition, these sorts of systems, when not developed properly, may allow people to move in and out of the system with relative ease, meaning a person can pay for coverage when they need it (say when a woman becomes pregnant) and stop participating when they are in relatively good health.  In other words, these people will only be adding stress to an already small risk pool, further hurting the financial viability of the organization.  This problem can be fixed, usually through a waiting period during which the person is paying into the pool but not able to utilize services, but these sorts of decisions should be made before a rural insurance scheme is implemented.