What is the core technology of testing?

Speaking of core technologies, I once mentioned in "multi-task data structures and algorithms" that the core technology of software is software design and data structure algorithms, so what is the core technology of testing?

There are a lot of technologies involved in testing, including testing management technology, testing defect analysis technology, test case design technology, and automated testing tools... is that the core technology of testing? I think the test case design technology and automated testing tools are the core technologies of testing.

Why is the test case design technology the core technology of testing? No matter what method or process is used, if a complete and effective test case cannot be designed at the end of the software quality assurance process, everything is useless and the quality is still poor, in addition, the management technology is basically open, and it is difficult for you to become the core technology, except for the management consulting company rather than the software and hardware company. The quality of software depends on the completeness of test cases.

Why is the automated testing tool also the core technology? We know that the mainstream core software, such as operating systems, compilation tools, databases, and various system software and tools, are in the hands of Americans. Most people in other countries are doing some application-layer tasks, or do some system-level applications at most. Because of this, automated testing tools will become core technologies in the future, just like software such as compilation tools.