Who is the test for?
When you're giving a talk it's important to know who your audience is and what they care about. When you're writing a test it's the same. A test is a message between developers, literally a coded message. So it's not just about the software it's also about the people, their relationships, and what they want.
Does your recipient just want basic trust before they invest their time? Then you need a smoke test.
Does your recipient have a limited brief to change a library but not its API? Then you need a unit test.
Are you trying to show a customer that their pet peeve you fixed last week is still fixed? Then you need a regression test.
Does your recipient just want to see that two teams actually talk to each other? Then you need an integration test.
Like giving a talk, it clarifies a test to think about the audience, their needs and capabilities, and what you want them to take away.
Biting the hand that feeds IT
