When I mention changing things up, I'm referring to not asking for the same repetitive task over and over I.e. If you're working on teaching a horse flexion to the right, you wouldn't want to keep making them give to the right over and over and over again for an extended period of time without a break or at least something else to do in between. This applies no matter what method you're using, and clicker trainers and "traditional" trainers can both get caught in this trap. Sometimes clicker trainers can get so caught up with what's going on they don't realize that, even though there's a "reward" involved, the horse REALLY doesn't want to be doing the same repetitive motion over and over again. Of course, traditional trainers that aren't being wise can pull and release a horse's head the same way over and over and over again, and even if the horse makes progress initially, it can be undone by frustration and the horse will quit giving to the pressure and resist it instead.