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Buyers and sellers sometimes haggle too hard and therefore fail to trade. Desirable joint projects are sometimes not undertaken because the projects¡¯ beneficiaries fail to agree how the costs should be shared. Sickness insurance, for example, is typically criticized either for offering too little coverage or for inviting misuse. In either case, the basic problem is that people have an incentive to economize with their private information: some insurancy-policy sellers claim that their costs are high in order to increase the price; some beneficiaries of joint projects such as insurance-policy holders claim that their benefits are low in order to reduce their own contributions to the project; some well-insured workers claim that they are sick, in order to reduce their workload.
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