Here's an example of why:
The Gresham's Law of Law - Law & Liberty
by Mike RappaportAnd then there's administrative law. Just as Constitutional Amendments don't happen due to Supreme Court rulings, Congress leaves most rule-making up to unaccountable bureaucrats.
In economics, Gresham’s Law is the law that say “bad money drives out good money.” In law, there is a similar law – deviant or problematic lawmaking drives out orthodox or legitimate lawmaking. This occurs in both constitutional law and administrative law.
Let’s start with constitutional law. The law of the Constitution is supposed to be established through the constitutional enactment process and the constitutional amendment process. Yet, it is well known that the Supreme Court does not always follow this legitimate method of constitutional law making, and instead changes or updates the Constitution through judicial lawmaking.
It is sometimes thought that these two types of lawmaking can coexist, but it has become increasingly clear that this is not the case. Since the New Deal, and especially as the Court has engaged in more judicial updating, the constitutional amendment process has atrophied. The main reason is that a constitutional amendment can only pass if it is supported by a consensus of the country. And developing a consensus may take a long time and may require compromise.
Go read the whole thing, like I said, it's short.