What is one disadvantage to a national policy that must be implemented by one agency of the federal bureaucracy?

There are numerous parts of the U.S. federal government in which a single agency is wholly responsible for implementing a policy. One primary disadvantage of that singularity is if anything occurs that disables or severely hinders that agency from doing its job, the policies cannot be implemented. Federal agencies receive their funding through congressional authorization so any hold up in that funding can slow or stall bring the agency’s operations.
One good example of this type of disadvantage relates to the Internal Revenue Service. National policy mandates that Americans file federal income tax forms annually. In December 2018 – January 2019, however, the federal government was shut down by executive action, and most IRS workers were furloughed. This became a problem in January when people began to file taxes and there were very few IRS workers available to process the forms submitted.

While there are many advantages of forming and implementing policy at the federal level, including protection of minority rights, uniformity of national regulatory standards, and increasing trade and job mobility, there are some issues which do need to be handled on the local or state level.
First, economic, social, and environmental conditions vary from state to state. Issues concerning water rights and usage in the arid southwest are quite different from those in the humid southeast. Racial and economic issues are complicated by the legacy of slavery in the former confederacy, while in many western and southwestern states, Native, Hispanic, and Asian American populations are more significant minorities. States such as Kansas and Iowa need policies to cope with rural depopulation, while many east and west coast cities need to address rising inequality and housing and other resource shortages due to an influx of immigrants from other states and countries. No one set of environmental or economic policies can address these varied issues.
Although having a single bureaucracy, instead of multiple, handle policy can simplify paperwork, it also eliminates checks and balances and can lead to overly close and even corrupt relationships between the bureaucracy and the industries the bureaucracy claims to regulate. Having multiple agencies involved serves as an important set of checks and balances against complacency and corruption.

The most important disadvantage to having centralized national policy instead of local policy is the inability to adapt to local circumstances. In any society, local regions are going to differ from one another to greater or lesser degree, and if their needs differ strongly enough, national policies that are one-size-fits-all could be ineffective or harmful.A good example of this is minimum wage. Prices vary substantially between different regions within any large country; for example prices in San Francisco are much higher than prices in rural Tennessee. A federal minimum wage that is fixed at a nominal dollar figure like $10 or $15 could have very different effects in those two places; in San Francisco it might be beneficial in helping people afford the high prices, or not even matter because wages are already above that level, while in Tennessee it could be harmful as it requires paying unreasonably high real wages in some industries.It is sometimes possible to design federal policies that work around this problem (in this case, you could set a minimum wage at purchasing power parity), but often a better solution is simply to allow local governments to make their own decisions on certain issues.
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