The magical universe that J.K. Rowling created for her Harry Potter series has bewitched hundreds of millions of fans around the world. Over the past couple of years, she’s done her best to expand our knowledge of the wizarding world, through plays like Harry Potter and the Cursed Child and this month’s prequel, Fantastic Beasts and Where to Find Them. As fans, we gobble up every shred of information we get because it helps make the world she’s created feel just a little bit more real.

Though Rowling has done an incredible job creating the characters and locations that bring the Harry Potter franchise to life, there are a few logical pieces that have fallen by the wayside — magical fallacies, if you will. They’re head-scratching gaps in her magical lore, gaps in plot that make us stop and think, and little bits and pieces of the story that just don’t quite add up. Here are 15 Things About Harry Potter That Make No Sense.

15. Wizarding world currency

harry potter wizarding money 15 Things About Harry Potter That Make No Sense

It is a credit to Harry Potter creator J.K. Rowling that she was able to create an entirely new monetary system — but perhaps math wasn’t her strong point, because when it comes to wizarding currency, the numbers don’t always add up. Throughout the entire series, Harry Potter and his friends routinely pull out knuts, sickles, and galleons to pay for everything from their school supplies to a butterbeer at the Hog’s Head.

We know, thanks to some savvy HP fans, that a galleon is about $25, a sickle is roughly $1.50, and a knut is somewhere in the neighborhood of $.50. All that is well and good… until you add up what Harry Potter characters paid for basic day-to-day items. Then the system starts to break down. Your basic Hogwarts textbook costs three galleons, which sounds reasonable, but a wand from Olivanders — aka an item full of prized items like unicorn hair and phoenix feathers, and the one essential item you need to, you know, cast spells — is only seven galleons. That’s less than $200. When you add to that the fact that an owl seems to cost something between six and eight galleons, it becomes really difficult to understand how exactly wizards decide the prices of the items they use on the regular.

14. The purpose of a Remembrall

harry potter neville longbottom remembrall 15 Things About Harry Potter That Make No Sense

One of the best parts about being a wizard in the Harry Potter universe seems to be that there are all kinds of spells and items to streamline your life. With the flick of your wand, you can instantly retrieve out-of-reach items. A quick trip to a wizarding candy shoppe will equip you with a sweet treat that will make you sick so you can skip out on exams.

With all these helpful items, it seems downright silly that the Remembrall was invented at all. The glass sphere turns red when you’ve forgotten something, which sounds convenient enough. Here’s the rub, though: it doesn’t tell you what you’ve forgotten. In other words, it’s the magical equivalent of tying a thread around your finger as a visual reminder to remember something important — great in theory, but often way more frustrating than not remembering that you’ve forgotten something in the first place.

13. Dumbledore letting Harry keep the invisibility cloak when Sirius Black was on the loose

harry potter invisibility cloak 15 Things About Harry Potter That Make No Sense

In Harry Potter and the Prisoner of Azkaban, the whole wizarding world was on high alert after Sirius Black escaped from prison. The Ministry of Magic went out of their way to keep a watchful eye on the Boy Who Lived, because they were all sure that his godfather, the aforementioned escapee, was out for his blood. Why, then, didn’t Hogwarts’ ever-so-wise Headmaster consider revoking Harry’s easiest and best means of moving around the castle without detection as soon as he arrived on school grounds?

During his first year as a Hogwarts student, Dumbledore gave Harry a unique gift; an invisibility cloak that once belonged to his father. Common knowledge would tell us that a wizard as intelligent and insightful as Dumbledore would think to put a moratorium on its use — at least while Harry was in peril, right? Not so much. As a result, Harry was able to duck in and out of Hogsmeade and around school grounds, and very nearly lost his life — though not at Sirius’ hand, at least.

12. The Weasley twins should have seen Peter Pettigrew on the Marauders Map

harry potter weasley twins marauders map 15 Things About Harry Potter That Make No Sense

Fred and George Weasley, though not exactly studious, were two of the most industrious students to ever roam the halls of Hogwarts. During their seven years as students, they made it a priority to learn every trick that the castle had to offer, thanks in large part to the Marauder’s Map, a magical piece of parchment that revealed secret passageways, and also showed where everyone in the castle was located at any given time. They bequeathed it to Harry in Prisoner of Azkaban — and it was thanks to this map that he first became aware of Peter Pettigrew’s unexpected presence at Hogwarts.

That begs the question, though– since the man who betrayed Harry’s parents to Voldemort had been masquerading as the Weasleys’ pet rat Scabbers for years– how did Fred and George miss seeing him on the map? There’s no doubt they would have checked it on their brothers’ whereabouts from time to time — and realized that first Percy, and eventually Ron, were perpetually followed around by — and sometimes sleeping with — a man named Peter. Even if they didn’t know the rat’s history, they should have easily figured out that their unusually wizened family pet was more than he appeared.

11. Wizards learn no essential life skills at Hogwarts

harry potter ron weasley crystal ball 15 Things About Harry Potter That Make No Sense

There’s no doubt about it — going to school to learn how to do magic would be freaking awesome. Harry, Ron, Hermione, and the rest of the students at Hogwarts learned how to transfigure objects, fly on broomsticks, take care of magical creatures, and make powerful potions. Unfortunately, they didn’t learn much in the way of practical skills — which makes it difficult to understand how they might be able to function in the world.

Thanks to J.K. Rowling, we know that before young witches and wizards head off to school at age 11, they stay home with their parents. Presumably, they learn enough reading and arithmetic to be able to complete their coursework — but once they’ve donned their robes and been sorted, the non-magical learning most certainly grinds to a halt. Now, we’re not saying that Hogwarts grads should be able to do calculus, but given that some, if not all, will at some point have to interact with the real world, it seems a little impractical to forego any further refreshers on some basic life skills.

10. Why there are spectators at the Triwizard Tournament

harry potter triwizard cup 15 Things About Harry Potter That Make No Sense

The Triwizard Tournament was designed to promote magical cooperation across Europe — and in Harry Potter and the Goblet of Fire, it was great for building bridges. Unfortunately, it wasn’t quite as effective at actually entertaining the people it brought together. That’s because, of the three events designed to test the mettle of each school’s champion, only one was even remotely watchable. Sure, it would be exhilarating to watch young students outwit dragons, but after that, it’s baffling that the tournament would even invite spectators.

The second task of the Triwizard Tournament took place underwater in the Hogwarts lake. The anxious supporters of Viktor Krum, Fleur Delacour, Cedric Diggory, and Harry Potter could only sit and wait for them to emerge from the watery depths below. The final task was even less interesting — unless your idea of fun is staring at the thick outer wall of a tall hedge maze. So while the students of Hogwarts, Durmstrang, and Beauxbatons saw new friendships and alliances form during the tournament, they didn’t see much else.

9. There’s seemingly always an identical number of students in each Hogwarts house

hogwarts houses great hall harry potter 15 Things About Harry Potter That Make No Sense

At the beginning of every school year at Hogwarts, a new batch of frightened first year students enter the Great Hall for the first time. They stand before their new classmates and are sorted into Gryffindor, Ravenclaw, Hufflepuff, or Slytherin — and somehow, the Sorting Hat always manages to place an equal number of students into each house.

Now, maybe we can believe that only a handful of wizards are accepted to Hogwarts each year. After all, most schools have an enrollment cap, right? Where it starts to get confusing, though, is when you consider that the Hat takes a student’s personality and personal preference into account. It seems unlikely that there would never be a group of students that yielded a higher-than-average number of Ravenclaws, or one that failed to produce a full class of Hufflepuffs. So it seems almost impossible that each house would be identical in size from year to year.

8. Harry should have been able to see the thestrals before his fifth year at Hogwarts

harry potter luna lovegood thestrals 15 Things About Harry Potter That Make No Sense

When Harry Potter headed back to Hogwarts in The Order of the Phoenix, he was confronted with an unpleasant surprise: the seemingly horseless carriages that transported him and his friends to their home were actually powered by winged, veiny, and menacing horse-like creatures that few others could see. They were thestrals, Harry learned — and they were only visible to people who’d witnessed death. There’s just one problem with these creatures showing up for the first time in the fifth book — Harry had seen death long before he saw thestrals for the first time.

It’s been argued that the infant Harry only heard his mother’s death, but if he was able to remember the sounds of her screaming when the Dementors closed in around him, that seems to be mincing words a bit. Even if we do contend that he didn’t officially see death until the end of the Triwizard Tournament, that still leaves one big logic hole. Harry and his friends would have taken the carriages back to the Hogwarts Express at the end of the school year, and just shortly after Cedric died. So wouldn’t he, at the very least, have noticed the thestrals then? Maybe he was just too overcome with shock over coming face-to-face with Voldemort. Or maybe it’s just a huge plot hole.

7. Voldemort’s entire plan to get Harry’s blood during Goblet of Fire

Voldemort1 15 Things About Harry Potter That Make No Sense

Throughout the entire Harry Potter series, there were signs that our hero and his nemesis, Voldemort, were inextricably tied together. In The Goblet of Fire, we got our first hint that they were bound by more than an Avada Kedavra curse gone wrong. He Who Must Not Be Named was slowly coming back from near-death — but he could only return to his full evil self by using Harry’s blood.

Though still physically weak, and obviously eager to get his plan for world domination back up and running, Voldemort went full Bond villain. He concocted an elaborate plan that spanned months, involved multiple players, and hinged entirely on getting Harry to win a tournament he wasn’t even supposed to participate in. In retrospect, it probably would have been easier for him to wield some of his influence with his Death Eaters and place a student or staff member in a position where they could get a blood sample from an unsuspecting Harry.

6. The absence of other country’s witches and wizards during the Second Wizarding War

second wizarding war harry potter 15 Things About Harry Potter That Make No Sense

In Harry Potter and the Deathly Hallows, there was a pretty clear line between good and evil. Those loyal to Dumbledore and the Order of the Phoenix stood on one side; Voldemort and his Death Eaters stood on the other. Since it’s clear that other wizarding communities outside of Britain would have been affected by the sudden rise of a half-blood hating demagogue, it’s hard to believe that no one else would have stepped up to try and put a stop to the Dark Lord.

Yet inexplicably, most of the rest of the wizarding world was nowhere to be seen during much of the Second Wizarding War, and most especially the Battle of Hogwarts. Sure, Fleur Delacour stood by her husband Bill Weasley’s side during the Battle of Hogwarts — but she was a rare non-British fighter in a sea of Hogwarts students and alums. While the good guys ending up winning in the end, there’s no doubt they would have benefited from a little back up from across the pond. So much for magical cooperation.

5. Why Lily and James weren’t each other’s secret keepers

harry potter lily james order photo 15 Things About Harry Potter That Make No Sense

One of the biggest tragedies in the Harry Potter series was the untimely death of James and Lily Potter — and when you really think about it, they probably didn’t have to die. Harry’s parents tried– and failed– to hide from Voldemort, who was searching out every wizarding baby in the hopes of putting an end to a prophecy that spelled his doom. They thought they were protecting themselves when they asked Peter Pettigrew to do a Fidelius Charm and conceal their location from the Dark Lord. Instead, being the exceedingly crappy person that he was, Peter betrayed the Potters and led Voldemort right to them.

At first blush, the whole tragic event seemed like a case of simply trusting the wrong person. However, we learned in Harry Potter and the Deathly Hallows that Arthur and Bill Weasley were able to successfully be the secret keepers for their respective hideouts, the Burrow and Shell Cottage. That means that, in theory, Lily or James could have done the same. If they’d been their own secret keepers, they’d likely have never been compromised — and may have survived long enough to see their son grow up.

4. Wizards probably wouldn’t need glasses

harry potter glasses 15 Things About Harry Potter That Make No Sense

Magical folk in the Harry Potter universe are able to control minds, alter their appearance, and transform into other creatures. So it seems like, at some point during the creation of all those magical spells and devices, that they would have thought of something that could keep their vision 20/20.

On the one hand, it’s hard to imagine a young Harry without his signature round eyeglasses, but on the other, he would have been at a bigger advantage throughout his years of dodging peril if he hadn’t needed to worry about keeping them in tact. Dumbledore’s half-moon spectacles were pretty cool, and Professor McGonagall looked especially severe when she peered disapprovingly at students over her frames. But aside from providing a discerning aesthetic, glasses seem like they’d be a completely unnecessary inconvenience for your average witch or wizard on the go. Even if magical law prevented altering basic biology, you’d think at the very least some enterprising shopkeeper in Diagon Alley would have developed magical contact lenses that fixed eyesight for good.

3. Voldemort not using the Unbreakable Vow with the Death Eaters

harry potter unbreakable vow 15 Things About Harry Potter That Make No Sense

It’s a powerful spell, designed to forever bind two witches or wizards to a promise. Severus Snape used it to seal a promise that he would protect Draco Malfoy in Harry Potter and the Half-Blood Prince. The Unbreakable Vow is an incredible oath that can be broken only in death. So why didn’t Voldemort use it more while he was attempting to rise to power? We know that he had no trouble using the Unforgivable Curses to torture and dispose of those who stood in his way. It’s a bit baffling, though, that he wouldn’t have taken more steps to keep a hold on the Death Eaters who swore allegiance to him.

If he’d employed the vow, Voldemort could have made sure that none of his minions turned against him or, more importantly, that they weren’t actively working against him in secret. He also would have had a pretty good idea any time someone like Snape, who worked as a double agent for years, wasn’t loyal, because they would have been super dead the second they turned on him. At the very least, the Unbreakable Vow was a pretty solid insurance policy — one that any Dark Lord should have considered if he was really serious about taking over the wizarding world.

2. How Bellatrix Lestrange got her wand back

harry potter bellatrix lestrange wand 15 Things About Harry Potter That Make No Sense

She was one of the most dangerous witches in all of the wizarding world. After spending years in Azkaban for torturing the innocent and aiding Voldemort, Bellatrix Lestrange broke free and resumed her rampage across Great Britain. We know that at some point, she was able to get a hold of the one instrument that would ensure she could go on to Avada Kedavra another day — her wand. After all, Olivander himself confirmed that it was her wand when Hermione, Harry and Ron brought it to him in The Deathly Hallows. The question remains, though — how exactly did she get the dang thing back?

Hagrid’s wand was destroyed by the Ministry after he was expelled from Hogwarts — so it seems as though magical law enforcement would have thought to do the same to an avowed supporter of the most evil wizard ever, right? Even if they didn’t destroy it, though, it’s hard to believe that Bellatrix would have been able to retrieve the wand right away from inside the Ministry. After all, it didn’t officially fall into Death Eater control until a couple of years after she escaped. Maybe there’s a simple explanation for her quick re-possession, but it would have been nice to know how she could get back to her evil ways so quickly.

1. Why parents send their children to Hogwarts at all

ron hermione harry potter hogwarts 15 Things About Harry Potter That Make No Sense

Hogwarts is a magical place that educated thousands of bright young witches and wizards. It had brilliant instructors who were dedicated to shaping minds and turning their pupils into upstanding magical citizens (for the most part, anyway). It also had a troll, a three-headed dog, an ancient evil basilisk, a tree that could kill you, a whole forest full of hungry spiders, and multiple teachers who either deliberately or accidentally put students in danger. At least once a year, it seemed, at least one student either died or came close to it. Once, an escaped murderer managed to sneak inside and make it all the way to the students’ sleeping quarters.

You’d think that, with all the bad news and mayhem that came out of Hogwarts, parents would have been a little more reticent to send their kids there year after year. We know there were other wizarding schools throughout Europe, so why send your beloved offspring to the one where their lives are routinely at risk?

What do you think was the most confusing part about the Harry Potter series? Let us know in the comments!

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