The way in which these two characteristics are brought together in video is in the story. Despite all of our sophistication, most of us adults still love a story. I'm going to guess that you've watched some of them to the end, even when you knew in the first five minutes everything that was going to happen. In this case, it isn't the story specifics that grab us. It's the desire to see the story played out, moment by moment.
Video has the capacity to engage students through the power of story.
Of course, badly done video stories may turn off viewers. Fortunately, the quality of training videos has been rising due to competitive pressures. As a result, there are more well-made, engaging videos around. Because of its dramatic content, video also has the remarkable capacity to provoke the emotions. No other medium, except perhaps live training, can quite equal it in this respect.