The question above asks a question that seems to coincide with one of the two main restrictions that the constitution places on the government before it can take private property. However, what is being referred to here as “public good” is actually referred to as “public use” by most courts and statutes.
A proper public use in North Carolina was defined in a test that the North Carolina Supreme Court created in Carolina Tel. & Tel. Co. v. McLeod. Generally, the test is whether the condemned property in question would contribute to the general welfare and prosperity of the public at large. Furthermore, the test was narrowed to only those takings which do all the functions already mentioned, but also furnishes the public with some necessity or convenience which cannot readily be furnished without the aid of some government power, and which is required by the public as such.
According to the tests above, the public benefit test, which is the basic test used in North Carolina to determine whether there is a proper public use, requires that the taking be for the general welfare and prosperity of the public at large. It also requires that the taking be for the purpose of providing necessities and conveniences to the public. It requires that those necessities and conveniences not be readily available without the assistance of the government.
Keep in mind, though, that this test is a basic test. There are further nuances to the test that would change how the courts react. In some instances, the courts would allow a taking for the benefit of only one person. However, in those instances, the courts will ask whether the taking’s paramount purpose is for the general welfare and the private benefit is merely incidental. If the opposite is true, then the court will find an improper taking.