privacy

I guess it means you have to cancel when your subscription is about to expire, because they won't refund you or let you continue to use the service for the period you've already paid for.

If you cancel before that they'll give you credits, which are useless if you don't want to subscribe to another product of theirs.

So you are force to cancel the subscription before the renewal time and hope you don’t forget to cancel it.

I think the author actually means "force to cancel right before the renewal time (e.g. during the 12th month of a 2 year subscription)" because cancelling earlier means losing the rest of the subscription (according to the author). And if you forget to cancel during that short window you'll be charged more money when it auto renews.