I've seen exponential learner mentioned a few times, but I'm not sure I understand exactly how that's supposed to be understood. It would seem like it's someone

I've seen exponential learner mentioned a few times, but I'm not sure I understand exactly how that's supposed to be understood. It would seem like it's someone who's rate of learning goes up, the more he learns, but I'm not really sure how that is sustainable. Could someone explain me the difference between an exponential learner and someone with a high, linear rate of learning?