Unlike Vulture's slapdash American Idol charts, it would appear that actual research went into the ones in What Not to Sing's in-depth study of how Idol contestants' success is affected by the amount of exposure they receive on the show. As it turns out, finalists whose backstories and early auditions are seen by viewers stand a much better chance of advancing to later rounds than the unseen singers who producers ignore. It's nothing we didn't already know, but it's certainly nice to have our suspicions confirmed by colorful charts.
Ever wonder why the producers don't show the backstory of every semifinalist? [What Not to Sing via Idolator]