Thoughts on TDD

The biggest advantage of TDD is that it looks at software from the perspective of use rather than development; it can generate better application interfaces.
The problem with TDD is that the software or business details are directly introduced.
Therefore, I think a software should have an overall design first. A specific function can be developed based on TDD. Another applicable scenario is that the overall requirements of the software are vague, TDD can be used to build a prototype for main business needs;

Unit testing and scrum:

The advantage of unit testing is that, with the accumulation of test cases, more quality assurance is provided for system modifications. However, with the increase of test cases, maintenance costs are constantly improved, especially in the scrum model, unit testing seems to be a weakness.