Usability. Just recently I went down a particularly deep rabbit hole when I tried to run Angular unit tests with a headless Chromium browser on a Jenkins CI server.
Suddenly I found myself having to debug various Docker images, Jenkins files and Kubernetes pods.
Not only are these tools often used indiscriminately, regardless of whether they're actually needed for the use case at hand but there frequently also seems to be an apparent disregard for the non-functional requirements of the people using them.
Sure, I can launch "kubectl" or "docker exec -it" to see what's going on but as someone who merely wants to run unit tests I shouldn't have to.
Talking as experienced front-end developer, currently working in an angular project, I must indicate that there are no Angular unit tests in existence. A unit test that requires a full browser to run is not a unit test, but a full e2e test. Exactly the same as the endpoint tests that require opening a server and binding to a port.
With Jasmine tests running with "ng test" (i.e. with Karma test runner rather than Protractor) the system-under-test usually is a single component, directive or service.
Therefore, conceptually these indeed are unit tests.
You could argue that because a browser environment is required for running these units the tests are integration tests.
Still, they're commonly referred to as unit tests (including the official Angular documentation).
Suddenly I found myself having to debug various Docker images, Jenkins files and Kubernetes pods.
Not only are these tools often used indiscriminately, regardless of whether they're actually needed for the use case at hand but there frequently also seems to be an apparent disregard for the non-functional requirements of the people using them.
Sure, I can launch "kubectl" or "docker exec -it" to see what's going on but as someone who merely wants to run unit tests I shouldn't have to.