A video or picture you publish is needed only until the networks have fetched it. Two days after a post goes out, its files are deleted from our storage: a small thumbnail stays in the queue and the live post is one click away on each network. Drafts nobody finished in a week lose their files too; the post stays and asks for the media again. Evergreen posts keep theirs, because a remake reuses them. Less stored, less to pay for, nothing you still need gone.