[ambrop7]

As has already been mentioned, there are industries where the code simply must have no bugs and in those code reviews will be different. Most critical components may be written by a very small team perhaps even a single person, as multiple people working on the same thing will generally result in more bugs.

Again I didn't say tests are a bad idea. In industry projects they are usually a very good idea. My point was that people should be able to write working bug-less code without using tests. When a test catches a real bug, it is to be understood as a failure of the developer(s).

[lisivka]

I saw so many bugs, so I switched from "code is working" by default to "code is broken" by default unless it proven that code is working correctly at target environment with required constraints.

Moreover, test cases are saving development time massively, so why waste time for manual tests and debugging sessions, when I can use computer to do that instead of me? When practiced regularly, test cases are written in tens of seconds. For example, if I will work on a calculator, I will write something like assertEquals(calculate("2+2"), 4, "Result of arithmetic addition is wrong."); Then I will work on calculator until this test will pass. Only then I may start to write unit tests. It's easy and fast, so why not?