I cannot agree more …
“The more you can divide up the behavior of your app into components, the more effectively you can test that the behavior of your code meets the reference standards in all particulars as your project grows and changes.
For a large project with many components, you’ll need to run a large number of tests to test the project thoroughly. Tests should be designed to run quickly, when possible, but some tests are necessarily large and execute more slowly. Small, fast running tests can be run often and used when there is a failure in order to help diagnose and fix problems easily.”
