What is the definition of first render in react native?

I am confused when will the first render happen开发者_开发问答. I tried following to figure it out.

//login.js
    useEffect(() => {
        console.log('first render');
    }, []);

I have navigation like this: login.js(console.log success)=>home.js=>login.js(console.log fail) Is that because I have navigation history of login.js which make it not first render?

Thanks!