Mostly anything a human can test, a machine can test even if it requires end-to-end UI-automation integration testing. If there's a test that's part of the suit

Mostly anything a human can test, a machine can test even if it requires end-to-end UI-automation integration testing. If there's a test that's part of the suite that is worth running every time something changes, it's simply a matter of cost: How much time will automation take, how long will the automation last, what is the cost of maintenance, is that less than the cost of a person doing it manually? People tend to be bad at forecasting these kinds of costs, its easy for prejudice for or against test automation to cloud one's ability to be impartial in the forecast.