Good sitcom writers have a way of making the most mundane and humorless setups into real comedy gold. Take a classic show like Frasier, which revolved around a super-pompous psychiatrist (Dr. Frasier Crane, of Cheers fame), his even-more-super-pompous brother, their old dad and, dad’s physical therapist Daphne Moon. Does it sound hilarious?

Of course it doesn’t, but the dialogue is just fantastic and the jokes come abundant and fast. Not only that, but the show manages to pull off something that The Simpsons was once so good at (while the fans still liked the show): blending silly slapstick moments and cheap toilet humor with comedy of a more ‘sophisticated’ level: wit, wordplay, clever references, that sort of thing.

Anyway, though, we’re here to talk about The Big Bang Theory, a show that also tries to blend silly moments and cheap jokes about Leonard’s gassiness (caused by his lactose intolerance) with intelligent humor from the world of advanced physics. You won’t hear the words ‘advanced physics’ and ‘humor’ in the same sentence very often, friends.

Over its long run, The Big Bang Theory has enjoyed a lot of mainstream success, much more than a show based on this niche premise could ever have really expected. Nevertheless, it’s also attracted a lot of criticism for its characters, their attitudes, and their portrayals of certain stereotypes.

Let’s take a look at some of the worst offenders here, as well as two of the characters that redeem the show. Don’t worry, there won’t be a theoretical physics test at the end. There will be character-specific spoilers throughout, though, so watch out if you aren’t up to date.

MAKES NO SENSE: Dr. Beverly Hofstadter

As fans will know, the gang’s various parents pop up at regular intervals throughout the show’s run, and… well, things tend to go all kinds of awry when they do.

It’s dysfunctionpalooza around here, and that’s never plainer than when Leonard’s mother Dr. Beverly Hofstadter pops by for a visit.

For one thing, the cold, calculated characters in sitcoms really need to dial things down to avoid being downright unlikable, and Beverly hovers around that line just a little too much at times. Her relationship with Leonard is just rough to witness at times, especially considering that she manages to bond (in her own ‘unique’ way) with other members of the cast along the way.

Heck, she probably would’ve smuggled Sheldon home in her handbag and kept him for her own, if he wasn’t so darn tall.

MAKES NO SENSE: Barry Kripke

Part of The Big Bang Theory’s whole shtick is trying to present ‘nerds’ in all their multi-faceted glory. Yes, the show tells us, they collect comic books and viciously debate on fan forums at 4 am, but they’re also super smart, productive, and lovably socially inept. There’s an endearing vulnerability about them, through the show’s lens.

Barry Kripke doesn’t quite fit in with this image. When the boys’ Caltech colleague makes an appearance, it’s usually to be vindictive to Sheldon or for the audience to have a cheap laugh at his speech impediment (comedian John Ross Bowie, as we reported on CBR, has one in real life, but plays it up for laughs on the show). It’s often tough to see what he really contributes.

MAKES NO SENSE: Jimmy Speckerman

The show is often criticized for resorting to tired old stereotypes, and Jimmy Speckerman brought a lot of that into sharp relief. Did you know that the academically-inclined and physically feeble among us are sometimes bullied at school? Thanks for that doozy of a revelation, Big Bang.

As we’ve reported previously, the character was super uncomfortable to watch, completely unrepentant for his past misdeeds. Not only that, but he was portrayed by Lance Barber; the very same Lance Barber who plays a certain father in Young Sheldon.

Yes, this is one of those little TV facts that we’re not supposed to question too deeply, but Dr. Cooper revels in that sort of thing, and he’d definitely make note of the fact that this guy looks exactly like his late father.

MAKES NO SENSE: Dr. Sheldon Cooper

Speaking of Sheldon Cooper, it was inevitable that the persnickety physicist was going to have his own spot in this rundown. After all, he’s the probably the best-known and most popular of the gang (in real life, that is). He may be completely insufferable, but Jim Parson’s star turn as the character has earned him all manner of awards and accolades.

Do we love Sheldon, or do we love to hate him? Everyone’s going to have a different opinion there. He’s a real anomaly, and that’s just the thing: he isn’t consistent. Sometimes he’s horror-struck by others sitting in ‘his spot,’ and sometimes he doesn’t even comment on it. Sometimes he needs a carefully-chosen seat in someone else’s home, and sometimes he silently plonks himself anywhere that’s free.

He makes mistakes, too, such as the time he claimed that striking a wine glass produces a B flat note (it’s actually a B).

MAKES NO SENSE: Anu

As the show winds down for good (that’s right, friends, we’re in final season territory here), fans who have been watching for over a decade want closure. We want to know, as with Friends and countless other beloved sitcoms, where the characters are going to end up.

For Raj, life has been one heck of a ride. Romantic life in particular.

The awkward astrophysicist has been in relationships with all kinds of colorful characters, and his arranged marriage with Anu seems a little let’s check him off the list, we’ve only got so many episodes left.

By sitcom standards, she’s a very prim, proper and straight-laced sort of person, and it’s tough to imagine her integrating with the gang in the same way that Amy, Penny, and Bernadette have over the show’s run.

MAKES NO SENSE: Stuart Bloom

Since his introduction as the owner of the boys’ favorite comic book store, Stuart Bloom has been quite the divisive character. He’s one of those who’s too important to be considered a mere side character but doesn’t quite make the cut with the main cast either. A position that suits Stuart as we know him pretty darn well.

That whole ‘relationship’ with Howard’s mother, his position in the Wolowitz home, the crushed and defeated demeanor… in sitcoms, you’ve got to be careful with the laughing with somebody/laughing at somebody ratio, and poor old Stuart hasn’t been treated well in that sense over the years.

As with Hans Moleman of The Simpsons fame, things can get a little uncomfortable when you play the let’s laugh at this person’s misfortune card too many times.

MAKES NO SENSE: Larry Fowler

As we’ve seen, the parents of the main cast make quite frequent appearances throughout the show’s run, and they definitely make their presence felt whenever they do. When Amy Farrah Fowler became Sheldon’s one and only, it became clear that her parents had to be thrown into the mix as well.

What a disastrous duo they are, too. Larry Fowler, Amy’s long-suffering, quiet, and downtrodden father, was brilliantly played by Teller (of iconic magical partnership Penn and Teller). The casting was incredibly apt on all levels, as Larry is rendered silent, completely controlled by his domineering wife.

Perhaps it was simply a case of having to do something new with the Fowlers that we hadn’t already seen in other Big Bang Theory parents, but everything that happens between them in “The Conjugal Configuration” is more unsettling than funny.

MAKES NO SENSE: Leonard Hofstadter

When we first meet Leonard way back in the very first episode, he seems set to be a ‘toned down’ version of his roommate. Dr. Hofstadter may be a brilliant physicist, serial user of complex jargon, and comic book enthusiast, but he struggles with Sheldon as well. Leonard’s meant more as a middle-ground character, it’s probably fair to say.

As the series progressed, though, his insecurities and flaws came more and more to the fore. His pining after Penny was one thing, but once the two did get together, he was incredibly controlling and even downright rude to her at times.

Perhaps these traits aren’t his fault (look at his childhood, his mother, and everything else), but many fans struggled to connect with Leonard as much as they did with the rest of the core gang as a result.

MAKES NO SENSE: Howard’s Mother

Ah, dear old Mrs. Wolowitz. Much like the Golden Snitch in a Quidditch match in the Harry Potter series, she was a super useful plot device. The Golden Snitch could bring a match to a convenient end whenever it’s been dragging on a little too long on the page, while Mrs. Wolowitz could raise a cheap laugh with a single shout from off-screen whenever needed. What a tension-breaker!

The issue with Howard’s mother was, she never really evolved beyond that. Like Leonard, she had terrible controlling traits that made her a little unlikable at times, and her always-unseen gimmick was effective but had been seen before.

Her sad demise later in the series brought some emotional weight to proceedings, but the character had very little positive impact on the show outside of that.

SAVED THE SHOW: Penny Hofstadter

Penny’s role in the overarching Big Bang Theory universe is a crucial one. It was established very early on that she’d be the lens through which we view and understand her extraordinary, scientific genius neighbors and their gang.

It’s the same role that the companion occupies in Doctor Who. She’s not ‘inferior’ to these geniuses by any means, bringing something equal and valuable to the table as well.

Her presence makes the whole main cast more diverse, and more well-rounded people as a result. That’s the idea, anyway.

The would-be actress may not grasp a lot of the science jargon that’s used over the takeout table, but where would her friends be without a dose or two of her pop culture knowledge? She’s a vital cog in the Big Bang Theory machine, and the show would have been lost without her.

MAKES NO SENSE: Ramona Nowitzki

As we saw with Leonard’s dear mother, sitcom characters who are supposed to be pretty darn unpleasant aren’t anything new. In these sorts of shows, after all, all kinds of embarrassing situations crop up, and it’s nice to see that happening to people who deserve it (rather than poor, misguided Stuart… again).

Ramona Nowitzki just doesn’t quite fit that criteria. She was certainly obnoxious, pushing Sheldon harder and harder to work and leave his friends behind, but she did have his best interests at heart (in a controlling and slightly worrying sort of way).

The real issue is that Nowitzki completely overstayed her welcome, returning to the show much later and… well, not doing anything to improve our perception of her. Surely you’d get the message after that Sheldon’s not interested in you in about a nanosecond?

Let’s not forget that she actually had the gall to suggest that Sheldon share credit with her for a discovery she helped him to make.

MAKES NO SENSE: Priya Koothrappali

Priya and Leonard’s relationship was a bit of an odd one, for a whole variety of reasons. For one thing, it actually lasted a decently long time, which is unusual for any of the Big Bang Theory boys. For another, it just never sat quite right with the audience.

Friends fans will remember the whole Rachel and Ross thing, and how every misguided relationship they both embarked on was just gut-wrenching. Priya wasn’t particularly rude to the group or unpleasant as a character, but she was a roadblock on the way to Penny, and fans don’t take kindly to that sort of thing.

Besides, she was Raj’s sister, her parents didn’t approve of the whole thing and she was vastly different to the rest of the gang. It was quite relieving when she moved back to India.

MAKES NO SENSE: Neil DeGrasse Tyson

Over the course of its long run, The Big Bang Theory has seen quite a lot of high-profile guest stars. Everyone from Charlie Sheen to Stephen Hawking has appeared on the show (there’s a good trivia question; what do those two have in common), and they’ve made some big coups along the way.

One guest star you may not have expected to see is Neil deGrasse Tyson, who appeared as himself in the episode “The Apology Insufficiency.” Tyson is the director of New York’s Hayden Planetarium, and Sheldon immediately took issue with him when he came to Caltech. In his view, Tyson had been personally responsible for Pluto’s demotion to dwarf planet status, and Sheldon liked Pluto. Ergo, he did not like Tyson.

For his own part, the astrophysicist does his best to explain that he did not personally demote Pluto (the International Astronomical Union voted on that decision), and even personally apologies to Sheldon, but the stubborn scientist isn’t having any of it.

Later, in the season 12 premiere, Tyson reappears after getting into a Twitter argument with Raj. It all makes you wonder why he’d want to be the subject of science snark… again.

MAKES NO SENSE: Rajesh Koothrappali

If you’ve even dabbled in the show, you’ll know that the main cast all have their own unique set of hang-ups, insecurities and other issues (heck, who doesn’t). Of them all, though, there’s a case to be made for the fact that Raj is the most troubled of all.

For the first several seasons, his selective mutism rendered him completely unable to speak to women outside of his family, unless he’d drunk alcohol. Despite this, he went on to have more romantic dalliances than any of the other boys, even if they were short-lived and generally disastrous.

As the series went on, Raj’s behavior became ever-more unusual in some respects. He becomes attached to Howard and Bernadette to an unhealthy degree and that whole business with Siri? The less said about that, the better.

MAKES NO SENSE: Amy Farrah Fowler

Ah, the twists and turns of fate. Who would have thought that Howard and Raj creating an online dating profile for Sheldon (as a joke, with joke entries throughout, without his knowledge) would have ultimately resulted in the relationship-averse doctor eventually getting married?

Amy Farrah Fowler, like her husband, is one complex character. Her friendship with Penny (read: her adoration of her) is downright uncomfortable at times, and the demands she makes of Sheldon (which she should really know better than to make at times) is super confusing too.

Amy has a way of filling a gap in the group that the group didn’t really know it had.

That neatly defines her relationship with Sheldon, too, and makes her the hilarious, inexplicable, and tragic character that she is.

MAKES NO SENSE: Leslie Winkle

This is the issue long-running and super popular shows often have. People have very strong feelings about the core cast, they’ve gotten to know them over several years and they’ve bonded with them.

For one-off characters –or some that maybe recur a few times—to really be a hit, they’ve got to be consequential. They’ve got to add something to the show. Leonard’s short-lived relationship with Leslie Winkle just didn’t succeed there. If anything, it was just another vehicle for Sheldon to show off his social ineptitude (why’s that tie hanging on the doorknob), and a way to work one of Johnny Galecki’s old Roseanne colleagues into things (the character was portrayed by Sara Gilbert).

Later, in complete odds to her attitude in that relationship (to wit: not wanting one), she’s very forward and controlling with Howard, proving to be a manipulative and inconsistent character.

MAKES NO SENSE: Zack Johnson

Of all of Penny’s former flames, Zack Johnson is perhaps the most difficult to pin down. On the surface, yes, he’s one of those taller, stronger, not-so-hot-in-the-old-brain-department guys that Penny often went for, but he’s much more than that.

Affable to a fault, Zack is no jock. The group tended to make fun of him at first for his lack of intelligence, but he’s always interested and even enthusiastic about science. He’s a world away from Kurt, another ex-partner of Penny’s who was mean and aggressive.

While he has precious little in common with the gang (beyond that enthusiasm), Zack managed to worm his way into the inner sanctum on more than one occasion, which was quite an achievement for such an academically-challenged guy. Somehow, he even got Sheldon to apologize to him, and that’s not something you see every day.

MAKES NO SENSE: Charlie Sheen

As we saw with Neil deGrasse Tyson, there have been some distinguished guest stars over the show’s history. Here’s the other issue with that sort of thing, though: they’ve got to serve a purpose.

Friends had huge names like Brad Pitt, Bruce Willis, Danny DeVito, and Jeff Goldblum make brief appearances (all but Willis only were only seen in one episode), to a large extent simply because they could.

In The Big Bang Theory, Charlie Sheen does something similar. “In The Griffin Equivalency,” Raj tells what appears to be just another extra that he’s going to be in People magazine. The man turns to him, revealing that he’s Charlie Sheen, and says, “Yeah? Call me when you’re on the cover.”

It’s a neat little nod, certainly, but was it really necessary?

MAKES NO SENSE: Lucy

Lucy, again, is a tough character to define. During the course of season six, she embarks on a relationship with Raj, which seems to be starting to take shape before Lucy ends it during the season finale.

Was it a positive or negative experience for Raj? That’s the difficult thing. Lucy was beginning to open up to him, and, suffering from intense social anxiety herself, would have been a good fit for him. The break-up was devastating for Raj, but it seems to have been a watershed moment in terms of his selective mutism.

There was something both endearing and heart-breaking about this short-lived couple, texting back and forth at the same table. Ultimately, Lucy probably had a good influence on Raj’s life, even if she never really knew it.

SAVED THE SHOW: Bernadette Rostenkowski-Wolowitz

It’s often said that the right person can have an incredible impact on our lives, and Howard and Bernadette are an excellent example of that. The two met in season three (Bernadette’s first appearance in the show is in the episode “The Creepy Candy Coating Corollary”), and after a bumpy start and several huge bumps in between, eventually marry.

Prior to meeting The One™, Howard was a compulsive womanizer (in his own mind) whose attitudes to dating were all kinds of questionable. As he settled down to married life and becoming a father, he became much less one-dimensional, and a whole lot more likable.

Quite apart from doing the character of Howard huge favors, Bernadette has an important role in the group at large. Heck, if you can send Sheldon off to bed, you can do anything.