Those games who have any success with this model, btw?
Those who left the FOSS and pico-8 bubbles and got customers from outside.
The answer is pretty simple. In those communities, asking for compensation of your work (aka. asking for a price) is seen as unethical.
And yes, that's a hyperbole, but it's really not far off the truth.
It's seen as tone deaf, when those communities are 100% about sharing things for free.
So my suggestion: Use a proprietary license
I'm telling you these things, coming from a FOSS background and making pico-8 games.
I have experience with both and making "regular" games. And the community, you are posting into, matters the most.
Pico-8 and FOSS are not good ones. Heck, even itch.io I'd say is not the best (but the best we've got)
Steam might be better, because people are more used to paying for things, but the massive $100 hurdle and 30% cut is very discouraging.
Btw. itch takes 10% by default and you say what it gets.
Anyway, how to be successful?
It depends! You need a community or else nothing will go.
What do I mean by "community"? Well not the regular stuff of mutual aid, but more you need fans. You need people excited about your game!
How do you get people excited? Well, lots of things. Sharing art of it and having it about kinks worked well for me. But it heavily depends about what you want to do.
But let people know what you're doing. Otherwise they won't get excited about your work.
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