For 12 seasons, CBS’s hit comedy series The Big Bang Theory made audiences laugh and shot its stars (Jim Parsons, Kaley Cuoco, Johnny Galecki, Simon Helberg, and Kunal Nayyar) directly to the top of the Hollywood later. Earlier this year, the show ended and its stars tearfully parted ways.

But diehard fans of the show know that not everything was as it appeared to be in terms of plot holes and storylines. There were a lot of inconsistencies that seemed to run rapid throughout the show’s run. Despite winning numerous Emmy awards, we still have some questions for producers regarding some of these mistakes.

Here are 16 Big Bang mistakes that we can’t seem to forget or unsee every time we turn on a rerun (despite the show being over and done with).

16 If He Has An Eidetic Memory, Why Is Sheldon Constantly Forgetting Things?

It’s been known since day 1 that Sheldon Cooper (Jim Parsons) has an annoyingly keen mind. Sheldon possesses an eidetic memory, which means he remembers literally everything. So why are there so many scenes where he needs to create lists in order to remember stuff? Or when he can’t recall certain dates?

15 Sheldon’s Spot On The Couch

Sheldon always had HIS spot on the couch, and every character knew this and was annoyed by it. Yet, this only came to light when producers needed that particular storyline to revolve around a particular episode. Yet, you’d notice that other characters were CONSTANTLY sitting in Sheldon’s spot when he’s in the room and he seems to have no problem with it.

14 That Strange Elevator Paradox

One of the jokes in the show was the broken elevator (the group lived on the third floor of their building). How did the elevator break? There are different versions. In one, Sheldon blew it up to save the group years prior (and all witnessed it). In a different episode, Howard was trying to figure out what happened to the elevator despite WITNESSING it take place.

13 Like Howard Ever Would’ve Been An Astronaut

In season 5 of the series, Howard (Simon Helberg) got to go to space. First of all, NASA would have never allowed him out of earth’s atmosphere thanks to all his reoccurring health issues (like his arrhythmia and high-risk allergy to nuts). Not only that, but he was under investigation by the FBI at one point and that’s a huge strike against him.

12 Amy’s Ever Shifting Personality

Mayim Bialik joined the show after a few seasons as Sheldon’s girlfriend Amy. But you’ll notice that when her character first arrived, she was figuratively cut from the same cloth as Sheldon. But after a season, she started to change and her personality started to change dramatically. While notable changes happen over time when in a relationship, this one was drastic.

11 Wait…Isn’t Sheldon Allergic To Cats?

It’s wildly known that Sheldon has a lot of allergies (like Leonard) and him being deathly allergic to cats is one of them. However, in one episode after Sheldon and Amy break up, he ends up spiraling and getting a lot of cats to compensate. Yet, he has NO allergic reaction to them in this particular episode.

10 That “Girlfriend Clause” Doesn’t Really Hold Up

First of all, per the roommate agreement, no girls are allowed to spend the night. This is a rule EVERYONE BREAKS ALL THE TIME, including people that don’t even live in the apartment. The guys (sans Sheldon) are constantly trying to hook up with women AT the apartment and Penny spends the night all the time (even before her relationship with Leonard).

9 Penny’s Father’s Name

So, during season 1, Penny would often refer to her father’s name as “Bob”. At this time, we only knew tiny little tidbits about Penny’s life before Los Angeles (we didn’t even know her last name), yet in season 3 when her dad is actually introduced, his name is Wyatt. C’mon, producers.

8 They Have No Idea How To Use Salt And Pepper

If you didn’t notice, food is a huge part of the show (the group has all their important convos over dinner at Sheldon and Leonard’s as well as in the school’s cafeteria). There is always salt and pepper in front of them and they always appear to simply shake it over their food. If you look close enough though, you’ll notice they’re grinders, not shakers.

7 Sheldon Should Basically Be Dead After This Prank

One time, Sheldon’s arch-nemesis Barry Kripke (John Ross Bowie) filled a room full of helium as Sheldon was a guest on a radio program. Eventually, it altered Sheldon’s voice so that he sounded like a cartoon character on the air. Thing is, if a person is deprived for that long without oxygen, they would perish. Clearly, Sheldon didn’t.

6 Leonard Claims To Be Allergic To Wine But…

We all know that Leonard has a ton of allergies, and an allergic reaction to wine is one of them. He maintains that he gets massive headaches whenever he drinks wine. Yet… HE’S ALWAYS DRINKING WINE IN LATER EPISODES. Does he just treat the migraines or was he just a hypochondriac (which he is too)? We’ll never know.

5 Internet Explorer As Their Main Browser???

These characters are ALL tech geeks and they make of point of saying it a lot. Yet, whenever you see them working on their computers – the browser they use is always Internet Explorer. With as pretentious as they appear to be, why on earth would they use that extremely problematic browser? It’s just not possible.

4 How Big Was Howard’s Mom, Really?

One of the ongoing jokes in the show was that Howard’s mom is so big she can’t walk anywhere. Though, she constantly going places (like shopping, Howard’s wedding) and plus, if you take a look at the pictures lining Howard’s house, you’ll notice she was never big at all (she claimed she didn’t get big until men started courting her and bringing her candy).

3 Sheldon Often Breaks His Own Roommate Agreement

The supposed ironclad roommate agreement was put into place by Sheldon and often had to be followed by Leonard and Leonard alone. Yet, whenever Sheldon breaks a rule, Leonard doesn’t care. Like when Sheldon brought home all those cats (no pets in the apartment rule), Leonard didn’t even bat an eye.

2 Sheldon And His Simple Math Mistakes

Sheldon is a super genius and he constantly makes sure everyone around him knows it. However, if an eagle-eyed genius managed to take a closer look on those whiteboards the guys have all over their apartment, they’ll notice some simple calculation mistakes that no of Sheldon’s caliber would have missed.

1 Man, They Sure Eat A Lot Of Junk Food

Food has always been a huge part of the show. It’s what draws Penny over to the guys’ apartment in the first place. And it’s ALWAYS so heavy (Italian, Chinese) and yet, all you see them doing is pushing the food around their plates – both in the apartment, at the restaurants, and in the school cafeteria. Which would probably explain why their weights never change.

References: Screenrant.com, reddit.com, buzzfeed.com, cbs.com, youtube.com