The critical factor in determining whether something is produced as a public good is whether the benefits to society are greater than the total cost.
Public goods are characterized by two key features: they are non-excludable (which means that individuals cannot be effectively excluded from using them) and non-rivalrous (meaning that one person's use of the good does not diminish its availability to others). For something to be considered a public good, its provision should lead to benefits that exceed the costs to society, making it justifiable for the government or community to provide it when the market may not do so effectively.
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