The indie game world is very busy. There are a TON of games showing up, and that's a good thing, but it also means some gems will get lost in the clutter.
Your goal will be personal and defined by the parameters of your own individual project.
I've launched five paid asset packs on Itch plus a couple of tiny freebies, and have 100+ total downloads between all of my products, and well over a dozen payments [purchases] on the platform so far. My traffic on Itch.IO is far higher, it's in the thousands, across all my Itch pages, and these numbers, I hope, will only climb as a result of the Holiday sale I'm running which has some extremely deep discounts.
Success there right now would be a regular flow of buyers and accumulation of a few actual reviews/ratings as that's currently the main reason my views largely don't turn into purchases. People buy, and they like what they bought - I hope - but they generally don't take the time to rate.
As far as my GAME successes go, none in the 'game' category yet but I'll be posting a game in about three months (Miniature Multiverse) and given how much this cost me to develop, ie thousands of hours' time and about $1300 in cash, so I have two real metrics here.
$1300 in sales raised is target #1, the game project at least didn't lose me money. That's the minimum break-even figure.
Target #2 is around $4500, at which point I'm making almost as much as an indie dev as I've been making on mTurk per hour, and as I approach or even pass that mark I can seriously look at indie dev as a career and ditch the mindless work that is currently propping it up.
There's a ton of content in this project that nobody's really been shown anything of yet. I think when people see what I've done with this they'll be blown away. But I'm biased. Maybe my work just sucks and that's why things aren't selling. :P
Your goals are likely different - tied to the cost of your project and what you've put into it.
Every case is unique.