In reply to Jeff Chandler.

Semantically, "lifetime" and "unlimited" are different, that's true. But not in the practical world of WordPress plugins.

There is a plugin -- I won't name it, because this dicussion is not about it or its developers -- whose free version is currently downloaded on average over 400 times a day (around 12000 a month). Its Pro version costs an average of about $100 for unlimited use and updates.

I don't know the developers' financials, but if just 100 of those users upgrade to the Pro version each month, that's $10,000 per month or $120,000 per year.

The plugin has been around for years, and has always been sold by the same model. Updates are produced every few weeks. Every so often, someone tells them they should move to a different pricing model involving recurring charges. They clearly have no interest in doing so. Isn't it possible that they actually know what they are doing?