[dreeves]

Glad you pointed this out! We could add another check (though I'm sure it will almost always be moot) that you have to do something on Beeminder that only humans do to be considered active (either sign in or manually add data).

The more I think about it though, if you're not signing in at all then you'll almost surely derail before long, which means your graph will freeze and you won't be active any more, automatic data source or not.

In fact, it now occurs to me that this is an example of when it is fair to charge you for a month even if you weren't actively paying attention. It's like my example with SERPs.com in another reply here. If Beeminder is actively collecting data for you and storing it and graphing it then that's value that it's fair to pay for.

If you do entirely wander off then even with an automatic data source -- unless you set preposterously unambitious goals (don't do that!) -- you'll end up marked as inactive before long. So I think the spirit of auto-canceling is still being honored.