Story arc

An arc gives a viewer a reason to stay past the point where curiosity runs out. Something has to be at stake at the start, move in the middle, and land differently at the end, and the audience needs to sense that shape early enough to commit to it.

This works at two scales. Inside one video it separates a list of facts from a journey through them. Across a series it is the through line that makes episode four matter more than episode one. Non-narrative formats have arcs too. A tutorial starts broken and ends working, and a review starts on a question and ends on a verdict.