One wonders how Hogwarts is able to stay open considering the amount of secrets, double crossing, and nose-less people (Voldemort) attacking the school on a yearly basis. What's even crazier is that half of the school's professors are normally responsible for a lot of the bad things that go down at Hogwarts. The Harry Potter franchise deals with a lot of suspicious teachers. However, Hogwarts has an entire history of bad professors that predate Harry's time.
Not only have there been faculty members that are poor at teaching, but there's also professors that were responsible for helping Voldemort's rise to power. Check out the list to see the worst professors in Hogwarts history!
10 Gilderoy Lockhart
Choosing to take on the role as the Defense Against the Dark Arts professor seems masochistic. Everyone knows it doesn't end well. Gilderoy Lockhart is a teacher at Hogwarts during Harry Potter and the Chamber of Secrets. Interestingly, Lockhart is already a bit of a celebrity by the time he gets to the school. Lockhart is famous for writing numerous books that claim he has battled the world's more fearsome beasts. Although Lockhart tries to put up an overly confident facade, the students at Hogwarts quickly learn that he's a fraud.
Every time Lockhart must actually face a monster, he ends up losing. It turns out that Lockhart has been using a mind erasing spell on anyone who had discovered his secret. No matter how deceiving Lockhart can be, he still gets points for proudly proclaiming that his favorite color is lilac.
9 Professor Binns
If a ghost wants to be a teacher, does one pay him in fake money or just let him teach because saying no to a ghost would be scary? Either way, Professor Binns is a ghost that teaches the History of Magic. Maybe it's unfair to say the kids at Hogwarts hate Binns. However, students dread taking his class due to the fact that he's so boring. Binns is infamous for droning on about non-sensical historical facts.
Furthermore, Binns shows very little interest in his students and tends to forget all of their names. The guy's also zero fun. Hermione asks him about the Chamber of Secrets and he shuts her down. He tells basically tells her "Shut up. Myths are lame and so are you." Binns doesn't quit say that, but he does in fact tell her that he doesn't believe in the Chamber of Secrets.
8 Armando Dippet
It must be a prerequisite for the Hogwarts Head Master to have a gorgeous beard. This bearded silver fox in question is Armando Dippet. He had been the Hogwarts Head Master before Dumbledore took over. There was nothing inherently evil about Dippet, but he chose to neglect the obvious signs of Tom Riddle's evil nature.
In fact, Dippet ignored all of the rumors that Tom Riddle was re-opening the Chamber of Secrets. Tom Riddle's actions lead to a few deaths including none other than Myrtle Warren. Although Dippet is not remembered for being a malicious person, he is known for being someone who could have tried to stop Tom Riddle's early rise to power.
7 Severus Snape
Snape has a serious case of resting witch face. On the surface, it's easy to see what nobody wants Snape as their potions teacher. The guy will assign detention to anyone who so much as breathes. Also, it doesn't help that Snape takes out his own aggression on the students. It's not their fault that he never gets to teach Defense Against the Dark Arts.
However, we do hope that every single student ultimately learned about Snape's true intentions to protect Harry and hated themselves afterward. Alright, maybe that's a bit harsh. The point is that Snape rules even though he's kind of a mood killer.
6 Horace Slughorn
Wouldn't it be awesome if there was a Transformers action figure where Slughorn turned into an arm chair? This professor has an odd teaching history at Hogwarts. Slughorn had taught potions for many years until realizing that one of his former students, Tom Riddle, was actually Voldemort. Subsequently, he retires and goes into hiding. Dumbledore eventually pulls Slughorn out of retirement once Harry arrives at the school.
Slughorn seems to be a passive man, but he actually conceals a terrible secret. It turns out that Slughorn is the one who accidentally told Voldemort how a person becomes immortal. Slughorn had selfishly been hiding all those years to escape his own guilt. What's cool is that that Slughorn redeems himself by fighting alongside Harry during the Battle of Hogwarts.
5 Quirnus Quirrell
Has anyone ever wondered what Voldemort would do all day while he was hiding underneath Quirrell's turban? Quirrell's backstory is pretty vague. Apparently he's a half-blood. Should've known! What we do know is that Quirrell was the Defense Against the Dark Arts professor during Harry's first year. Initially, students seemed more so annoyed by Quirrell. A Defense Against the Dark Arts professor being scared of a troll seems fishy. We get why nobody likes Quirrell by the end of Sorcerer's Stone. The guy shares a face with you know who for crying out loud.
4 Barty Crouch Jr.
Anyone who compulsively wiggles their tongue around like some sort of British snake-man is probably up to no good. Barty (Bartemius to the ladies) Crouch Jr. takes a potion in order to look like an auror (wizard police) named Alastor Moody. The reason why Barty poses as Moody is so that he can pretend to be the Defense Against the Dark Arts professor.
Barty tries and ultimately fails to kill Harry during the events of Goblet of Fire. It turns out that Barty is both a death eater and the son of a famous auror. Barty is just another example of someone giving the Defense Against the Dark Arts a bad name.
3 Amycus and Alecto Carrow
The Carrow siblings look like the tethered (ten points for making a relevant Us quote) versions of the Weasleys. These two became prominent once Voldemort's death eaters took over Hogwarts in Deathly Hallows. Amycus becomes professor of the dark arts while Alecto teaches muggle studies. Rumors quickly go around that Alecto loves to torture all of the students who defy her orders.
Imagine Umbrige's wrath, but divided amongst two people. It also doesn't help that The Carrows are straight up cowards. They ran away and abandoned Voldemort during his first defeat in the early eighties. Isn't it weird to imagine Voldemort in an eighties acid wash jean jacket? The point is that The Carrows are garbage people.
2 Salazar Slytherin
Rumor has it that J.K. Rowling nearly used a Panda Bear as the animal to represent House Slytherin. However, using a snake somehow ended up making more sense for a name like Salazar Slytherin. Joking aside, Salazar is one of the founding members of Hogwarts and is pretty much an all around bad guy. If a person didn't know any better, they'd think he's almost the exact same person as Voldemort.
Salazar had been a huge advocate for the separation between muggles and wizards. In fact, Salazar desired to wipe out muggles and muggle born wizards alike. Since none of the other professors agreed with Salazar's radical ideas, he created the Chamber of Secrets and leaves the school. Let's not forget that the Chamber of Secrets contained a basilisk (giant snake) that was meant to kill anyone Salazar viewed as inferior. We're not so sure how well that plan ended up working out since it only took a twelve year old boy to kill the snake.
1 Dolores Umbridge
Before Split introduced the world to Patricia, there was Dolores Umbridge. The pink cardigan wearing witch is sent by Ministry of Magic during Harry's fifth school year in an effort to regain control of Hogwarts. Things immediately go South. Umbridge becomes the Defense Against the Dark Arts professor, but never teaches any of the students how to actually protect themselves. Moreover, Umbridge begins to implement so many rules within the school that everything starts to seem like a dictatorship.
Perhaps the worst aspect of Umbridge's reign is that she is physically abusive towards the students. This insane woman makes the kids carve up their own hands. Who can forget that she also attempts to run Dumbledore and Trelawney out of Hogwarts? Thankfully, Umbridge ended up in Azkaban Prison. Hopefully that's where she will stay the rest of her life.