The problem with public provision is that the task of ensuring that the government supplies the proper quantity and quality of “public goods” is itself a public good .. When the government supplies a product, paid for indirectly by taxpayers rather than by the direct recipients of the product, few have an incentive to spend the time and resources to make sure that the government supplies the right quantity and quality. If the theory of public goods is correct, relatively few people are likely to spend time and resources making sure that someone else’s education (or health care or justice) is adequate.
In other words, monitoring and controlling a publicly provided good suffer from the same incentive problems that caused the supposed undersupply in the first place. Because very few people will benefit noticeably from, say, saving millions of dollars spread across the nation’s millions of taxpayers, only a few people will have a direct interest in monitoring and ensuring good management of public agencies. Their inability to capture major benefits from their efforts is likely to cause their efforts to be undersupplied. As a result, the public good may be provided badly—oversupplied, undersupplied, or poorly supplied.
All these movements—private schools, home schooling, and charters—are attempts to bring competition into a system where it is lacking. They face significant opposition from teachers’ unions and school administrators, who can muster considerable political power at the ballot box. The opposition appears to be grounded primarily in self-interest, not in the theory of public goods, because even if education is entirely a public good and subject to government support, nothing in public-good theory suggests that the state must operate the schools.