The Weasleys' house burns down in one film and is standing in the next, and nobody says a word. All eight Harry Potter films ranked by how much they betray the book, a fight between the two at the top, and the reason faithfulness predicts nothing.
A ranking of the eight Harry Potter films by how far each departs from what its book meant, not how many pages it dropped. Chamber, Stone and Part One bundled at the bottom; Goblet, Phoenix and the ending Part Two changed argued in full; then the fight: Prisoner of Azkaban, which threw out the plot and kept the meaning, against Half-Blood Prince, which kept the plot and cut the meaning, both cases at full strength before they are placed at two and one. Then the trap: fidelity predicts nothing, and the three kinds of betrayal (a cut, a changed meaning, an invention) are what do. With the filmmakers' own reasons (Kloves, Newell, Goldenberg, Yates, Heyman, Cuaron), Rowling's veto and her favourite, the dance against the Burrow, and a rule for which betrayals to forgive. Every quoted line is from the films.
Chapters
0:00 The House That Did not Burn
1:03 The Count
1:54 Eight. Chamber. Seven. Stone
2:59 Six. Deathly Hallows Part One
3:59 Five. Goblet of Fire
5:19 Four. Order of the Phoenix
6:39 Three. Deathly Hallows Part Two
7:45 The Wand, Snapped
8:43 Two Left. Opposite Directions
9:18 Case A. the Good Kind
10:45 A Veto, an Approval
12:06 Case B. the Honest Kind
13:30 Who It Flatters
14:54 Two. Azkaban. One. Half-blood Prince
16:06 The Trap
17:26 Same Rank. Opposite Films
18:28 Three Kinds
19:48 The Rule
20:32 Sign Off