Hela is a literal god capable of nearly soloing the entire Norse pantheon, Malekith isn't doing much to her.
https://www.youtube.com/watch?v=YYMTQCZnw0M
Aku is a rare villain who is able to be both supremely comedic and supremely dangerous, malevolent and cruel.. he is the embodiment of evil itself yet is a child in many ways, with all the unpredictable chaos that comes with it.
Aku can be deadly serious one moment and a meme the next.. this is part of what makes him one of the most feared villains as well.. he's comedic but he's also extremely successful.
Unlike the clumsy Hook Aku has a massive success rate and only lost because of his own sadistic nature.
Terminator gave one of the funniest anti-monologue scenes.
"you just can't go around killing people!"
"why?"
"what do you mean why? you just can't!"
"why?"
Plus many villains are more or less archetypical beings rather than actual humans, they won't redeem, won't learn from mistakes, will usually keeping doing same thing over and over.. if they have some illness, they will stay "insane" forever.
With that in mind its easy to see that many villains aren't there to be "smart", they are there to be a plot device.
(this applies mostly to super-villains, obviously, though some examples exist in pretty much any other media (horror is full of them) ).
If villains were smart fiction would pretty much be like this.. (so some *are* smart, if writers allow them).
The problem of monologuing is usually when the hero is an author's pet and thus can never really lose even when it makes little sense for them to win, the monologue in these stories are cheap tactics to provide victory.
A much better example of monologuing is when the villain monologues while beating the life out of the hero, even if hero may overpower them at least villain is actively trying to destroy them and not standing in a room with a trap that is so complex or silly the hero can escape or some other trope.
Bane may boast but he also does so while charging and smashing with blows that could kill.. contract Clock King or Riddler, who gloats while also making complex traps that Batman can then undo.. making no effort to ensure Bats can't move, it's fine to gloat but only if you are also actively making sure your enemy doesn't have a chance to easily undo your work.
There's also a third and enjoyable type.. the "Simply So Powerful They Can Have Fun".. when a villain is near-omnipotent so can do whatever they want, they can monologue and so on while still being completely unstoppable.
https://www.youtube.com/watch?v=4h8NmjpiY1M
Meta-Reason: to act as an info-dump for audience as well as a plot device to allow heroes to survive and win in scenarios that are otherwise impossible even by fiction standards.
In-Universe Reason: similar to why criminal post their crimes online or show off doing criminal things.. lack of consequences and/or attention-seeking.. especially with villains like Joker etc who just keep coming back, they have no real lasting punishment.. heck, real serial-killers did similar and would send letters or emails etc mocking people or explaining their next crime (often getting themselves caught in process).. sociopaths are especially prone to mouthing off and never learning from their mistakes.
There are examples of villains who don't monologue and they are often treated as extremely dangerous to the heroes, funnily despite audiences often complaining about monologuing even said audience can react oddly to a villain who doesn't reveal their plot.
Just as people don't expect villains who just off the hero without an elaborate goodbye message or way for hero to escape - these type of villains are used sparingly because they are narrative-breaking by design (especially in media like comics etc).
Some exceptions are obvious, such as silent slasher killers such as Michael Myers or Jason - they sure don't monologue, they are just forces of nature half the time.
So audience knows the plot.. it's like why heroes always have this odd habit of talking to themselves or explaining the blatantly obvious.. it's an old technique of info-dumping upon the audience what the characters motives etc are.. kind of clunky in modern story-telling but much like the tophat-wearing "does evil for evils sake" stereotype or cackling madman trope it sticks around.
The entire Norse pantheon in God of War fit into this as well, all of them are victims of generational trauma and abuse by Odin, who was arguably even worse than Zeus in that he saw his own pantheon as nothing but tools for his own ends.
The Norse pantheon may of been warriors but they also showed signs of child-like qualities that were utterly ruined by Odin - the sad part is some of them only revealed that child-like qualities on their death-beds (Baldur: "snow").
Kratos is also incredibly sad.. kind of the running theme of God of War is how the cosmos is broken, Kratos can put it back together but it will always remain shattered to some extent.
This is (despite the fantastical nature of the game) a sad reflection of reality, you can't always "fix" things, often the best you can do is fight through the conflict and try to rebuild from whatever is left.. you can't restore what was lost.
The best part is Bowler Hat Guy legit is a sad character despite also poking fun at the trope of tragic villains.. he's also extremely under-appreciated as a whole.
https://www.youtube.com/watch?v=UszT_L4QWII
Just a follow-up as I fear many folk aren't aware of just how powerful Master actually is.. here is him doing another insane feat of power.. turning every living person on Earth into versions of himself.. again this is him outright winning.
There's far too many other examples but you can see why Doctor Who is often considered among the most powerful of fictional meta-verses for a reason.
The Master, because even the lowest-tier Doctor Who villain is complex-multiverse, The Master is outerversal (that means basically he can eat guys like Kang for breakfast) - the only reason Master ever gets beat at all is the Doctor is also an eldritch horror (they just happen to have "adopted" humanity and thus act as our protector).
The Master, at their peak, could wipe out all realities, all time-lines etc etc.. the Master is also ascended even among Time-Lords (themselves an entire species that transcends reality) - having no real limit on how many times they can come back.
Of course, being Doctor Who, even the insane levels of power Master has is nothing compared to a few other villains in the series such as the Black Guardian or Celestial Toy Maker.
https://www.youtube.com/watch?v=4h8NmjpiY1M
He effortlessly sends future humanity to wipe out current humanity, Master almost always succeeds in every evil deed (Doctor undoes it but this doesn't negate the fact Master outright wins in most stories before time-lines are saved again by Doctor).
"Faux Affably Evil is a term referring to villains who, at a glance, are similar to those who are the Affably Evil type, but with a lack of sincerity to their affable and sympathetic nature. Such villains are rarely, if ever wrathful or patronizing in front of the heroes, but they do not actually show genuine empathy towards others."
"do not actually show genuine empathy towards others"
As I pointed to an admin already this needs reworded because as stands, yeah, Faux's introduction is basically standard psychopathy rather than just "false pleasantry".. it outright states they can't show genuine empathy.. if that part is removed Faux would not have a problem as far as redemption goes.
Any character that can't have genuine empathy towards others is, by very definition, not going to redeem - the best case is they settle down for practical reasons, boredom or any other reason other than remorse... because you can't have remorse without some empathy.. you can't have redemption with remorse.
Don't lump psychopaths in with generalized anti-social disorders and don't glamorize sociopaths as hard to understand, both are extremely easy to understand because they are the absolute extreme of the anti-social spectrum.
A psychopath actively seeks to harm others and doesn't care how they do so, that is the definition - it is not, I repeat, NOT, the same as simple anti-social personality disorder.
Also this is about fiction, not hard real-world facts (don't try and lecture someone on mental disorders when said person has multiple disorders themselves, a few on anti-social).. this wiki classes personality disorders as separate from mental illness when in medicine they aren't.
A fictional psychopath almost always fakes kindness unless they have power to do otherwise, by the definition this site uses, if they do nothing to disguise their lack of empathy they are classed as a sociopath as it is written on the category page, again with no relevance to real-world conditions.
Or they do a game Peach and actively tease and prod both the hero and the villain into fighting for their amusement (I mean when you feel bad for Bowser you know things have got bad (mostly the infamous Odyssey ending but there's been a few others).)
Olive Oyle over at Popeye could also sometimes do this, teasing and prodding the naturally aggressive and dim-witted Bluto into fights, then having Popeye beat Bluto up only to dismiss *both* of them.
Let's just say those tropes have not aged very well.
Guys that kill and abuse others to "get the girl" are natural hate-sinks because it's sociopathic idiocy at its finest, what better way to ensure the girl you claim to romance will never want to be within ten miles of you willingly than going around beating or killing anyone that gets in your way?
It's the ultimate Stupid Evil move.
https://villains.fandom.com/wiki/Cal_Hockley
Cal also deserves a mention on any list of "hate-sinks but not PE"
As far as "hateable villains who aren't PE"... anything from Chick Tracts I find to be a thousand-times worse than most Pure Evil characters, mainly because Chick Tracts promotes some truly vile stuff so their "villains" are either hate-sink incarnate or literal victims of Chick's fanatical views of the world.