I think this shows a different understanding than for example we follow at Codeship. Tests aren't there to test our code, but to make our Users happy. e2e test

I think this shows a different understanding than for example we follow at Codeship. Tests aren't there to test our code, but to make our Users happy. e2e tests make sure we don't break features and are able to validate new features don't kill the most common workflows. Thus we can innovate quickly, build new features and refactor. This makes our users happy. Unit tests, controller tests or others are mainly an optimisation as writing an e2e test for every failure state is not an option. It's a different understanding of why we test, but makes sure we focus on the right things with it.