That's because the first intervention inevitably produces problems, which then require another intervention to fix those problems. That new intervention then produces a set of new problems, which then necessitates new interventions. The process continues until there is a complete government takeover of that sector of the economy.
The same principle applies to criminal laws of an economic nature that people ignore. To ensure that people comply with the law, the government enacts a police-state measure. But then people ignore that measure, which causes the government to enact another one … and another one … and another one. The end of the road is a giant police state in that area of the economy.
A good example of this double-phenomenon is immigration.
The original immigration intervention was simply a law that prohibited foreign citizens from entering the United States without the official permission of the U.S. government. This law, of course, was contrary to the open-immigration policy under which the United States had been operating for more than 100 years.
But the government did more than that. It also adopted a system in which the government would plan the movements of people into the United States. What would be the quotas for each country? What would be the qualifications for entry? How many total immigrants would be permitted to enter on an annual or monthly basis? The federal government would decide such questions.