Adding numbers to what redonihunter said, from our own catalogue of about 270 itch listings. Most of our visits arrive through itch's browse and tag pages, and a page that isn't indexed yet gets almost none of that. So zero sales on an unindexed page doesn't tell you much about the art yet. It mostly tells you nobody has seen it.
Two things we measured that did move arrival. First, an outside post in a listing's first week: our posted listings averaged about 4 views a day against under 1 for unposted ones, and past about ten days we saw no difference. Second, most of our outside visits came from reddit threads, so a post in a subreddit that fits the pack is a good first step once the pages are indexed.