Before the MS acquisition Skype was not completely free. It had subscriptions and you could buy credit to reach the PSTN, however it was not profitable. Money

Before the MS acquisition Skype was not completely free. It had subscriptions and you could buy credit to reach the PSTN, however it was not profitable. Money would eventually run out, as it happens to every company that keeps an unsustainable product alive. Of course we as consumers would love to have everything free, but someone is footing the bill.