Metallica drummer Lars Ulrich recently talked with Andy Hall and explained his thoughts on songwriting sessions with Metallica frontman, James Hetfield. He said (transcriped by Ultimate-Guitar):

None of us ever went to school for any of this shit. We met in the fall of 1981 and instantly clicked.

And somehow, even at that time, we found a way to leave egos at the door when we were writing. It wasn’t like, ‘I’m the drummer and this is my turf and he’s the guitar player and that’s his turf!’

There was this open kind of thing happening between the two of us and between our two respective instruments that led to what is probably a fairly unusual way of doing things but to a strong kind of approach.

It’s hard to articulate and intellectualize even though we’ve been doing it for 35 years because I don’t really know what other people do.”

You can watch the entire interview from below.