Over the course of twelve seasons, The Big Bang Theory showed us a fair few different relationships that each made hugely differing levels of sense. The most prominent of those relationships were the connections between Leonard and Penny and Amy and Sheldon.

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We’ve looked at a list of five reasons that each of these relationships don’t make a whole lot of sense, and probably wouldn’t work out in the real world.

Leonard And Penny: Their History

Leonard penny first kiss

If there is one thing that almost always spells disaster for a couple, it’s if this is their second shot at being together. Something must have happened to break them up the first time around, and in this case, something did. Leonard and Penny had broken up twice already, so these events could easily come back to haunt them later in their marriage.

Sheldon And Amy: How Amy Treated The Relationship Originally

Of course, Sheldon is almost always the problem in the Amy and Sheldon pairing. However, early on, Amy made a big mistake that Sheldon might not have picked up on. She presented herself as pretty much the same as Sheldon: she expected no intimacy and had no grasp of social situations.

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She did a full 180 within about ten episodes, and then expected Sheldon to change for her, with her often trying to convince him to do things she would never have done herself just a few weeks earlier.

Leonard And Penny: They Lack Common Interests

Leonard and Penny drinking coffee at home on TBBT

It might not be the be-all and end-all of a relationship, but surely a couple needs a few things they can do together? Penny is eventually quite accommodating of Leonard’s loves in life, and watches things like Star Wars with him, but she never really enjoys any of it. Leonard doesn’t even give the time of day to Penny’s interests, and it makes you wonder what they could do while sitting on the sofa in the evening.

Sheldon And Amy: They Also Lack Common Interests

Sheldon and Amy first meeting in TBBT

In exactly the same way, Sheldon and Amy are pretty much polar opposites when it comes to interests and hobbies. Amy likes playing the harp and watching Little House On The Prairie.

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Sheldon likes every facet of nerd-culture, and seems to have never listened to music in his life. The two never seem to be in a situation where they like the same things.

Leonard And Penny: The Mystery Of Penny’s Existence

Penny and Leonard's first date on the Big Bang theory

It isn’t something touched on very often in The Big Bang Theory, but Penny is never given a surname. Maybe this is addressed off-screen, but it seems like Leonard should look into Penny’s background, just to check there isn’t a reason behind this. Let's hope he did before they got married.

Sheldon And Amy: The Existence Of The Relationship Agreement

Amy seems to love it and pretty much cries as soon as Sheldon mentions its existence to her, but the relationship agreement is a creepy thing. It forces Amy into a contractual relationship, more akin to employment than love.

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It also forces her to do things like drive Sheldon around at any given moment, which certainly isn’t the foundation for a good and successful marriage.

Leonard And Penny: Leonard’s Expectations

Speaking of the relationship agreement; Leonard and Penny might not have one, but their relationship is still built on a lot of strange expectations. For example, Leonard’s default during the early days of their relationship is to simply explain things to Penny under the assumption that she doesn’t understand what is happening.

Sheldon And Amy: How Sheldon Treated Amy Pretty Much Always

Jim Parsons and Mayim Bialik TBBT

You’re sort of forced to overlook every single thing Sheldon Cooper ever does in The Big Bang Theory because he doesn’t know what he’s saying. But he does a lot of really terrible, unforgivable stuff pretty often.

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The way he looks down on everything Amy does for such a long time, or happily rejects her when he asks him to accompany her to a wedding are both very fair reasons to call the whole thing off.

Leonard And Penny: Too Many Proposals

Leonard and Penny in the hotel room talking on TBBT

If there is one thing that proves there is a problem in Leonard and Penny’s relationship, it is how long it took for the two to get engaged. Two proposals each ended up being the magic number. Think back to each time the other said no: they can’t exactly have been sure this was the perfect relationship for them.

Sheldon And Amy: They Have Very Strong Opinions

Sheldon and Amy at prom on TBBT

Beyond that, they both seem to pretty much hate the career of the other. They might end up teaming up and winning a Nobel Prize together eventually, but before that, Amy looked down on Sheldon’s work, and Sheldon looked down on Amy’s work. Surely some mutual respect is needed there?

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