At some time a project will arrive to this point in which test category to favor on the long run. A lot of developer say that if you want to understand how a project works just check the requirements, if there are no clear written requirements, then they say go ahead and check the tests, if there arenl no tests you are more than screwed and you have the possibility to either leave the project as soon as possible or to show a way how a project should be maintained and not just kept alive.
I have worked on projects where we had no tests, and I have worked on projects where there were a tons of unit and integration tests, but the unit tests were tautological, and the it tests were clearly not validating the requirements just the developers assumptions, which is still not enough for you to understand the project and be confident when you change something.
I’m keen on introducing cucumber based tests on any projects which has real business logic with proper scenarios and not just crud based apps