1.First, when Ron was completely useless during the Devil's Snare entanglement and had to be rescued by Hermione in The Sorcerer's Stone. In the books, he was the one to remind her to use magic, and the pair's strengths complemented each other perfectly.
2.When movie Ron agreed with Snape's harsh comments toward Hermione in The Prisoner of Azkaban. In the book, Ron absolutely dragged Snape.
3.When Ron was a blubbering, incomprehensible mess during the spiders scene in The Chamber of Secrets. Book Ron was still scared, but was able to work through his fears and be brave like any true Gryffindor.
4.When Harry's insensitivity toward Ron's concerns about his family in The Deathly Hallows was basically cut out, making Ron's completely out-of-character behavior seem even worse.
5.When movie Ron acted like a smarmy, overconfident bro before his duel with Hermione in The Order of the Pheonix.
6.When Ron, instead of Harry and Hermione, blathered on to Dumbledore about Peter Pettigrew in The Prisoner of Azkaban. He even had to be helped out by Hermione, because Ron was never allowed to know what was going on.
7.When Hermione automatically knew what a mudblood was in The Chamber of Secrets movie and Ron just sat there throwing up slugs.
8.When Hermione said this line "nastily" in The Order of the Phoenix book, but it came across jokingly in the movie because movie Ron was a hapless moron and everyone knew it.
9.When Hermione was tortured by Bellatrix in The Deathly Hallows, book Ron was "half sobbing as he pounded the walls with his fists." Movie Ron didn't seem nearly as bothered.
10.When Ron had to be walked through helping Harry against the troll in The Sorcerer's Stone like an absolute buffoon. In the book, he Wingardium-Leviosa'd the troll's club by himself, and it was a super awesome moment for his character arc.
11.In the Prisoner of Azkaban book, Ron stood on his broken leg to tell Sirius Black twice that he'd have to kill him before he killed Harry — because he's a total badass. In the movie, Hermione defended Harry while Ron just whimpered in the background.
12.When Ron, a character who came from a big wizarding family and who had been flying brooms for years, hit himself in the face during their first Quidditch lesson in The Sorcerer's Stone — because movie Ron literally could not do anything right.
13.When Hermione, instead of Ron, was the one to tell Harry that Dumbledore had told them not to write to him in The Order of the Phoenix — showing that movie Ron and Harry just weren't the BFFs they were in the books.
14.In The Prisoner of Azkaban book, Ron pushed Harry out of the way when he thought that Sirius was attacking him. In the movie, he was dragged into the Whomping Willow like a helpless rag doll.
15.At the end of The Deathly Hallows, when Ron just hung out silently in the background while Harry and Hermione discussed finding the horcruxes.
16.When movie Ron insulted Hermione to the point of tears after the Yule Ball — and then just left her crying on some stairs like a total asshole — in The Goblet of Fire. In the book, it's Hermione who storms off.
17.Finally, when Harry told Hermione and Ron that he was going to go to Voldemort in The Deathly Hallows, and Ron just sort of loitered in the background like he didn't care about Harry, his best friend.
Think that the Harry Potter movies were more than fair to Ron? LMK in the comments!