A friend of mine on Facebook posted this video example in an ABA page and I thought it was a great way to showcase how powerful the science of behavior can be. In this particular clip, the learner, a girl with profound intellectual disability, is learning to walk. The narration says she has never walked, but in the span of a few hours, she is walking independently. (The language is horribly dated and we, as a field, have moved on from those terms, but this was over 50 years ago.)
What I find so powerful is the motivating operations working here. Her desire for the ice cream is driving her to learn behavior she had not previously learned. Reinforcing those successful approximations toward the ultimate goal gets here there in just a matter of hours. This shaping of her behavior is literally reinforcing the baby steps toward what she needed to be doing.
This is exactly why I do what I do. These kinds of success stories mean a lot.