actually the brain part comes in diagnosing a vehicle with a no start situation. Not a bad starter.

When I get a vehicle with a complaint it doesnt say diagnose the failed part.

It has a complaint and I have perform tests and diagnosis to find what part failed.

Thats called diagnosis.

You are wrong.

If the dealer stated a starter then so be it. They are ones that have to spend the time on their dime when they made the wrong diagnosis.

Dealer techs make mistakes all the time. Its just when they do they are eating the diagnosis and installation of the part quite a bit. Its happened to me. Sometimes misinformation or skipping a step can lead to misdiagnosis.
sometimes without a known good part you are shooting in the dark for example when its either a part or an ecu and the wiring is good.