I also write in a wholly linear style, and never from a plan, so there is nothing 'left out' in that sense. But if I go back and read the story again, there is always something that isn't in there that informed the writing but doesn't matter to the plot so isn't on the page. as an example from my meme, in the Thelma and Louise story I wrote, Louise called Thelma but never let the phone ring every day for nearly a month after she was raped in Texas. She never told Thelma, and mostly the story is from Thelma's POV (and wow, what a mess of POV I made in that, but never mind), and so it's not there. But I still knew it.