Some type of emotional charge should be provided every 10mins – this generates engagement; emotional engagement. This is achieved by making the story relatable. If I can relate to the story, it will generate an emotion which generates an engagement (source: John Medina, Brain Rules; Attention).
It can be anecdotes, case studies, it can be fun, scary or even embarrassing as long as the story stimulates an emotion which connects the audience to the material being presented.
The 10 minutes rule is a proven scientific fact backed up by research. Put out a topic, break it down and finish with a hook or story at the end of each 10 minutes lapse time.
Always start with the big picture. You can also start with a compelling story before going into the presentation material.