The adaptation problem is really a translation problem

What separates the screen works that endure from the ones that feel like illustrated summaries is whether the filmmakers identified what the source material was doing structurally and then asked what the screen forces you to confront differently. Compression isn't loss, it's rhythm. Visual grammar can carry thematic weight that prose accumulates across hundreds of pages. The adaptations worth studying are the ones that understood the original deeply enough to betray its surface faithfully.
Source: The 10 Greatest Movies Based on Books, Ranked ↗