One of the reasons why Europe has a much more all-encompassing welfare state than the USA is that in the US government services are poorly run. Whether it's providing healthcare , building high speed rail , or Issuing Drivers Licenses, the typical American's experience with government services is one of incompetence, corruption and failure to innovate.
There are lots of plausible explanations about why this might be. Maybe the US is too big to govern effectively. Maybe our two-party political system is uniquely polarized leading to gridlock and a lack of progress. Maybe government service isn't glorified by society, leading all of the would-be competent managers to pursue careers in finance or Silicon Valley.
Yet, there is one government service in the US on which every single person depends, which serves hundreds of millions of requests every day, and which does its job virtually flawlessly for less than its European counterparts. Every single difference mentioned above would apply just as much or more so to the USPS. Our political system hasn't been particularly favorable to the USPS. The US's expansive geography should be more of a hindrance to mail than almost any other service. And postal work is far from glorified in the US social consciousness.
So, why is the mail so much better than every other government service in the US?
If we could answer this question, could we use the answer to fix the rest of the government?
A couple of theories:
1) Culture of competence:
Not only is the mail famous for its motto "Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds", but it is also the one of the few government services enshrined in the constitution. Perhaps its unique foundational values create a culture that "the mail must go through" that lends itself to promoting competent leadership.
The weakness here is that it seems like an overly large effect. If a motto could really produce competent government, why hasn't anyone come up with one for other agencies? Why is it only Europeans who can "make the trains run on time"? Doesn't anyone believe "Veteran's deserve the best health care possible"?
2) Political Immunity:
Yes, the USPS is a political football. But it's less of a political football than almost anything else, because nobody is really against mail. Even its competitors benefit to some degree from having a uniform system of addressing and delivery so there isn't much of a lobby to kill the Post Office like there is with something like Obamacare.
All in all I consider this one a toss-up.
3) Measurable Outcomes:
If the mail stopped coming tomorrow, everyone would immediately notice. If even 1% of the mail started getting lost every day, the economic consequences would be sudden, dramatic and widespread. Bills wouldn't get delivered, checks wouldn't come in the mail, people would be upset. This instant feedback allows the USPS to continually innovate and improve.
The strongest argument against this is that lots of other government services are measurable too. Utilities, for example, and yet plenty of those are poorly managed.
Same a measurable outcomes but repeated for emphasis. The USPS delivers a product that consumers pay for. They compete (at least somewhat) with other businesses. And they are self-funded (more or less). If there is one thing American culture does well, it is running businesses at a profit.
Again, "but utilities" is a good counterargument.
PS. The USPS may not be the only competently run organization in the US Government. The TSP is one government program that pleasantly surprised me for being logically implemented and well-run. I've also never heard of anyone complaining about the US Mint. The Park Service has more issues than either of these, but is still generally well-run.