You could say "if you're offering a lot to a lot of people" then donations might work. At the same time you could be charging as well, and even though this adds

You could say "if you're offering a lot to a lot of people" then donations might work. At the same time you could be charging as well, and even though this adds complexity, it also adds a business. Charging does reduce popularity in the short term and chances of going viral. I suppose it's generally the most altruistic that give a to a website. It's not like you're curing diseases or saving lives, generally.