I think this sums it up quite nicely. The intent, which is encouraged by all branches and is culturally engrained (I will retrieve citations if requested), is "reduce your taxes as low as possible".
With the right advisors, corporations can do this very effectively. This should not be a surprise to anyone. They will pay less, much less. After all, that's what you encouraged them to do.
If your aim is to collect more taxes, then why encourage those being taxed to seek to reduce their tax liability as low as possible?
Forgive me if I am missing the obvious. But this to me has never made sense.
It's not something that's "encouraged" or "culturally ingrained." It's simply a matter of lowering your costs.
Maybe "encouraged" and "engrained" were not the right words. How about "endorsed"? I think rational self-interest is a concept that might vary in the degree to which it is adopted into people's behavior as you move from country to country. That's only a theory. Certainly, in the US, reducing tax liability, and doing so vigorously, is believed to be the rational thing to do.
But if I'm the taxing entity, is it rational for me to endorse the idea of paying less? That would seem to lead to a reduction in the amount I will collect as those being taxed adopt and refine their tax reduction strategies.
It's rational for you to accept the fact that people will work to minimize their tax liability and construct policy under that assumption.