That's not entirely true. They did charge something tiny to use the app (I think it was ~$2/year) but in many countries (outside the US where they were much more popular) they didn't block users who didn't pay. If you didn't want to see annoying reminders you would just pay and get rid of it. Many people I know never paid.
i paid for whatsapp back in 2012. it was a paid app on the app store. it wasn't much - $1, and everyone had to pay for it to download. later they made it a free app. i am more than happy to pay for a messaging app for myself and my close family, and i dont like the idea of sharing the data with fb. there needs to be a paid alternative.
I had paid for at least one year (just $1), may be two (don't remember exactly). I would be glad to pay more, but Facebook played a big game and now we're all stuck with it because at least in India WhatsApp is almost a necessity.
Thankfully in Russia it is not. Some people prefer it for some reason but there's no hard requirement to have it to be a part of society. I haven't even bothered to set it up on my new phone I bought a month ago and there was no discomfort resulting from that. Though I do still need to download my data and delete my account so people won't even try messaging me there.
They didn't monetize it because in countries like India if you were to monetize it most users would stop using the app. This I guess is the alternative. Thing is there is no reason to believe others apps won't do the same in the future.
