Comment by zdc1
It's another version of how gym memberships get you. Everyone errs on the side of over-committment and they get to make more money.
I've found I'm better off paying extra for a shorter duration until I've validated that I'll be using my subscription in 3/6/12 months from now. E.g. recently with Duolingo I ended up only paying for it on a monthly rate for about 4 months, and that wasn't even because I'd quit learning, I'd just found a much better app.