The Harry Potter books were first adapted to the big screen in 2001 with Harry Potter and the Sorcerer's Stone. Over the next decade, the subsequent books were also adapted into films. This meant audiences grew alongside the cast and characters during that time, which cemented its memorability.
Like most book-to-movie adaptations, the writing and stories underwent several changes to fit the movie's runtime. Unfortunately, with such an extensive book series, there's no shortage of alterations that wound up being for the worse. Several important character moments, universe rules, and plot lines were sidelined, which caused various inconsistencies.
10 The Attack On The Burrow Served No Purpose
In the sixth book, Harry Potter and the Half-Blood Prince, Harry spends the holidays with the Weasley family. While there, he meets the new Minister of Magic, Rufus Scrimgeour, who convinces him to become the poster boy for the ministry, which Harry doesn't take well.
The movie omits virtually anything implying this plot line. Instead, it replaces it with a scene where the Death Eaters attack Harry and the others at the Burrow. The moment comes and goes with little to no impact. Although its intention was to showcase the Death Eaters' looming threat, it's nothing audiences didn't already know.
9 The Build-Up For The Quidditch World Cup Was For Nothing
The beginning of the fourth book, Harry Potter and the Goblet of Fire, saw Harry and his friends attending the Quidditch World Cup. The book described the event as colossal and faster than Harry's usual Quidditch matches at Hogwarts. Given what viewers saw of Quidditch in the previous films, there was a lot of intrigue about how it would translate to film.
The movie initially gives substantial build-up for the Quidditch World Cup, only for viewers to see nothing of it. Given how the sport had less prominence onscreen from this point onwards, virtually any game footage would have been a great way to end the sport's appearance on a high note.
8 Cho And Harry's Break Up Is Less Reasoned
In Harry Potter and the Order Of the Phoenix, Harry falls for Ravenclaw Seeker, Cho Chang. Nonetheless, they break up due to neither approving of the other's friends, particularly when Cho's friend, Marietta Edgecombe, blabs to the Ministry about Harry's secret organization dedicated to teaching Defense Against the Dark Arts.
The movie shows Cho spilling the beans to the Ministry, which is what makes Harry break up with her. However, her expression when Dumbledore's Army is outed implies she told the Ministry begrudgingly. This is proved when Professor Severus Snape reveals the truth-telling potion, Veritaserum, forced Cho to tell on her classmates, thus making Harry a tad less likable. It's especially questionable given Harry didn't notice Cho's absence from the organization's final meeting.
7 Barty Crouch Jr.'s Role Is An Afterthought
Part of Goblet of Fire is one giant mystery regarding who entered Harry into the Tri-Wizard tournament and why, and who is behind various strange events occurring in the wizarding world. However, it all leads back to Barty Crouch Jr., who posed as a schoolteacher and was thought dead. Crouch reveals every part of his plans, thus tying everything together. But before testifying, he suffers a Dementor's kiss, which leaves him worse than dead and his plans unknown to the public.
The film omits or alters several of the strange events that happened before and at Hogwarts in the books. Crouch gets outed in the end, only to return to the wizard prison, Azkaban, with none of the characters curious about his scheme.
6 Wormtail's Demise Is Glossed Over
At the end of Harry Potter and the Prisoner of Azkaban, Harry laments how time travel failed to save his godfather, Sirius Black, as the man who framed him, Peter Pettigrew (aka Wormtail) still escaped. However, Dumbledore claims Harry sparing Wormtail's life will come in handy later. This is proved true in book 7 when Wormtail's silver arm turns on him after he tries to strangle Harry.
In the movie adaptation, no such thing takes place. Instead, Wormtail is hit with a spell by the house elf, Dobby, and nothing more is seen or heard of him. This alteration makes Harry's words seem accurate despite being assured otherwise.
5 The Gaunt Family Is Written Out
In Harry Potter and the Half-Blood Prince, Harry and Dumbledore look into a series of memories to explore Lord Voldemort's past and figure out the key to defeating him once and for all. Most of those memories involved Voldemort's family, namely on his mother's side, the Gaunts.
However, the movie omits every member of the house of Gaunt, leaving only two memories seen in the book. The omitted memories carried a lot of interest for readers, and the teen romance plots that took their place in the film didn't do the same for any part of the fanbase.
4 Voldemort's Death Felt Less Haunting Than Intended
By the climax of Harry Potter and the Deathly Hallows, all of Voldemort's Horcruxes are gone. Thus, it comes down to one last showdown between Harry and Voldemort to decide the fate of both the wizard and non-magical worlds. Harry emerges victorious, leaving a definitely dead Voldemort.
This climax was more or less the same in the movie, except Voldemort creepily disintegrates upon his death. In the book, Voldemort dies just like any other person. The book's version held more weight as it showed that, despite all his attempts to achieve immortality, he had little to nothing over anyone else.
3 Harry's Reason For Staying With The Dursleys Is Never Explained
After the death of his parents before the beginning of the series, Harry had no choice but to live with his abusive relatives, the Dursleys. Every summer following a Hogwarts term, he returned there, despite there being several wizarding families who'd happily take him in.
Towards the end of Order of the Phoenix, Dumbledore reveals to Harry how his mother's sacrifice created a blood protection that keeps him safe from Voldemort. However, it only works alongside Dumbledore's own magical protections if he considers the place he stays home. The movies neither mention nor hint at this revelation, and the later films show little if any sign of him being at the Dursleys, which makes it questionable to non-book readers why he ever goes there.
2 The Marauders Receive Little Exploration
In Prisoner of Azkaban, Harry receives an item called the Marauders' Map, which tells the owner where anyone is in Hogwarts Castle. Harry later discovers the map's creators are people he knows all too well with one of them being his father, James.
The movie never addresses how James and his friends as the ones who created the map (making it confusing how Harry knows Pettigrew as Wormtail in the fourth film). The map was a big part of Harry's growing connection to and perception of his father and those James knew. The movies make it out to be yet another powerful magical item, and it sees little use beyond its debut.
1 The Portrayal Of Snape Was Too Heroic
In the third act of Deathly Hallows, Snape meets his end at the hands of Voldemort. Afterwards, Harry witnesses his memories, which reveal several things such as Snape's past with Harry's family (most notably his mother, Lily), the plan for Dumbledore's death, and the revelation that Harry is a horcrux.
The movie makes out like James stole Lily from Snape and Snape loved her his whole life, which is far from the truth. The film makes little mention of the circumstances that led Lily to end her friendship with Snape, nor what made him turn on Voldemort. It makes Harry naming his kid after Snape seem justifiable, which isn't the case.