With those stats, even with just 4% of people wanting to learn, and just a fraction of them actually paying, that would be dozens of thousands of paying customers. Even at 1USD per month, it seems a relatively sustainable business.

Yeah, I think he is confusing "non-profit" with "non-payment". You can have a non-profit company with paying customers. I think he need to take a basic economics class.

I think the tone of this comment is unnecessarily condemning (apologies if I am reading it incorrectly) – I can totally understand why someone who has worked for years on a non-profit business which has created a lot of value for people (I think exercism is pretty good software) might want to be able to at least pay themself.

Non-profit doesn't mean you didn't get to pay yourself. It just means that any revenue that exceeds expenses must be reinvested into the business.

That sounds like Amazon to me.

Except amazon shares would be worth much less if there was a promise of no dividends ever

Thanks, yeah. New product will hopefully mean I can keep funding and growing exercism. They're very synergistic and will support each other.

Charging people $1 on sign-up would probably lower that 96% metric