I seem to recall the idea was that they keep your terms up to date with evolution of services you rely on (i.e. when you compose the ToS you select Google Analytics, S3, Facebook, Mixpanel etc, and appropriate clauses are included, and kept up to date as third party update their own legal stuff).
Hi guys, part of iubenda here. First, we know we have to work on driving a couple of points home.
There's a free, yearly or monthly subscription. The subscriptions really just divide a bigger chunk of money into smaller very affordable bits.
If you need the basic, free bit, perfect. Otherwise the SaaS system is in place for us to deliver a sophisticated service at very little up front cost. If you keep using it you get the updates pushed right to your app. The license can be reused on new projects, too.
the terms don't change and I can't think of any good reason to pay monthly, except of course that iubenda makes more money that way!
not everything needs to be crammed face first into an SaaS model