Paying means that the provider doesn't have to mine your email for keywords in order to display targeted ads (yeah, I know Google theoretically stopped doing this recently). So perhaps "your own" in the sense that another entity isn't accessing it.

> So perhaps "your own" in the sense that another entity isn't accessing it.

Do they have a spam filter? If yes, how do they filter emails without accessing it?

You're the customer, not their product.

But the data is still not in your control. Right?