Poster for the President's Birthday Ball, an official event associated with the birthday of President Franklin D" poster
The pattern
This still is filed under Problem-agitate-solve.
Define
Name the problem, make the cost of leaving it felt, then present the way out as relief.
Mechanism
Tension then release. The offer is not an interruption. It is the only door once the cost of staying is clear.
Verdict
The problem is known but not yet urgent
Why it works
It contrasts the joy and mobility of the dancing couple with the dark silhouette of the child with a crutch. This visualizes both the problem (infantile paralysis) and the aspirational solution (dancing again) in one image.
Steal this when
You are fundraising for a cure or recovery effort and want to show the stark contrast between the current suffering and the desired outcome.