Yes, this article is correct. I have also been saying this in comments on this site. Automated tests should be on the right level to provide value. On a level t

Yes, this article is correct. I have also been saying this in comments on this site. Automated tests should be on the right level to provide value. On a level that is too low, one ends up with tests that test implementation details or the highly interesting feature that the list type in the standard library of your favorite programming language is still capable of adding elements to itself. On a level that is too high one ends up with fragile tests where there is a lot of state to initialize before anything can be tested. Tests can occur on any level but they should be on a level that makes them interesting, which generally means that they test a property of the system that the customer could recognize as something they value. Most tests should maybe test how between one and five classes work together.