A recurring trope in Bittersweet Candy Bowl, with Lucy's true feelings towards Mike for starters.
In Boyfriend of the Dead, the Twins are nearly killed by Alex before N can explain that they are just harmlessly reenacting The Shining and not actually after anyone's flesh.
Cursed Princess Club: Princess Gwendolyn receives some solid advice from the Cursed Princesses on how to deal with Prince Frederick and diplomatically break off their engagement, but her delivery ends up a little muddled. When she actually finds Frederick and has her conversation with him, she's struggling to hold back tears (which leaves her eyes red and bloodshot) and has a terrifying grimace/forced smile on. The situation is not helped by Prince Frederick's mistaken assumption that he had accidentally frightened Gwen off a cliff that morning (it was actually Princess Monika, wearing Gwen's dress, and she turned into a crow before she hit the ground so there was no harm done). Gwen walks away thinking she's given Frederick a tactful way to escape their unwanted engagement, while Frederick gets the impression that Gwen is an undead witch who's just promised to haunt him for the rest of his life.
In Dan and Mab's Furry Adventures, Aaryana nearly kills Dan because an Oracle's vaguely worded answer strongly implied that Dan killed her beloved mentor Destania aka Dan's mother. The misunderstanding is immediately cleared up by Dan's sister before any murder happens. Later in one strip, the characters wonder why Oracles are always so vague; the last panel reveals that the cryptic bullcrap act is mandated by the Oracles' Union.
Dongtae doesn't tell Eunju that he's a Dicer, responsible for the Dice appearing in the school, and that he will be rewarded for protecting her (even if he wanted to do so regardless) until he couldn't hide it. Despite saving her from the school gang, she becomes mad at him the next day, though apologizes later.
Dongtae deals with renegade Guild members who "abduct" Eunju's club members. Despite having bloodied clothes, he neglects to explain to Eunju, who is against violence, why or that that choir club weren't in danger, further hurting the relationship with her. He explains to Mio why he has missed the date, but only after she got mad at him.
Dongtae has more information about the Dice than anyone else from combined Byungchul's, Taebin's and Mooyoung's accounts, but neglects to tell that to his allies until it becomes crucial, appearing not very trustworthy.
This is averted by Justin when confronted with an angry, incomprehensible fire monster; his first response is to try and work out a way to communicate, rather than go straight to beating the tar out of it. It attacks anyway, but it's the thought that counts.
When Magus regains physical form, he expresses his belief that an unconscious Ellen would rather be male, and that he wants to help with that. He says "We're running out of time. I'd rather not do it this way..." and aims a spell at her, prompting Elliot to tackle him and begin fighting. It turns out that Magus meant that he needed to forcibly wake up Ellen (which could cause headaches and nausea, hence why he'd rather not) in order to talk to her and confirm that she wants to be male before doing anything else. When Elliot points out that it sounded a lot like Magus intended to transform her then and there without her permission, he admits that yeah, it was understandable to take his words that way.
Also actively defied later on when Sam sees that this is happening on a space station he's sent to and all but drags the two parties involved into sitting down and talking about the problem.
In "The True Story Of That Girl", had Sujin actually talked with Aram, she wouldn't have been driven with envy and started a rumor of cyber-bullying her.
In "The Story of Brothers", had Mingyu and Minseo actually talked things out, Mingyu wouldn't have taken his stream stunts to great extremes to the point of death.
Much bloodshed could be avoided if certain main characters (most notably Agatha Heterodyne and Baron Klaus Wulfenbach and his son Gilgamesh) simply sat down and talked to each other. Instead, distrust and misunderstandings lead to characters fighting each other and working at cross-purposes when they could be allies, while the real enemy gets away. On top of that, every last one of them is either a Mad Scientist or a creation thereof, both classifications of individual not normally known for their ability to think on a level we usually call "normal", let alone communicate on it.
Poor communication started an escalation of distrust between Barry and Klaus, which is the cause of much of the later grief. Barry and "the Clays" hid Agatha from Klaus for eighteen years because they believe he is a servant of the Other. Upon discovering Agatha's identity, Klaus is very suspicious because she was hidden from him for eighteen years, so she orders her locked up and sedated. Punch and Judy take this as further proof of his ill intentions and fight back.
The entire Sturmhalten story arc, fitting for the introduction to the backstabbing Sturmvarous family. Even years later, fans have some difficulty figuring out exactly what happened because Tarvek spent the entire arc lying to basically everyone. Tarvek deliberately sabotaged Agatha's holographic message to the Baron, which she intended to use to explain how her mother was the Other and had possessed her. Instead, the edited message made it sounds like she was accusing the Baron of being the Other. And Dimo apparently forgot his previous conviction that the Baron should be informed ASAP about the Geisterdamen with the Hive Engines leaving Sturmhalten through underground tunnels. Various characters have pieces of the puzzle, but crucial information is not relayed. If only they shared this information, they could easily resolve their problems. At this stage, Baron Wulfenbach would dissect Agatha, seeing as how she's possessed by the Other and all that's holding her back is a single flimsy amulet. As Gilgamesh said, "let's be fair: He does have cause". Furthermore, a lot of grief might have been saved had DuPree actually sent a device team down to analyze Agatha's transmitter in Sturmhalten, instead of just joking about doing it and then bombing the damn thing.
Exemplified in this comic, where the wrong impression is given simply because the relaying party has a different perception of the words, and thus gets the meaning wrong. On the other hand, that example is subverted on the very next page, when Agatha makes it clear that she doesn't trust the Castle's interpretation of the scene.
What probably makes the problem worse is that the Big Bad is very good at sowing deception and hostility within groups. She is the most obvious root of mistrust between Barry and Klaus, while the problems caused in later chapters were most definitely due to the Big Bad's moles and hidden supporters along with secretly mind-controlling first Agatha and then the Baron.
However, they eventually could compare notes with Gil, making him the guy who knows the most about what's going on. Gil was the only party Klaus and Agatha both have reason to trust and who would be in a position to MAKE them both listen. Except that Klaus ended up either convinced or compelled to pretend that Gil is wasped.
This almost causes major problems in a side story taking place after the main story is completed. Hadrian Greenclaw returns home to Mechanicsburg to discover that the heads of the major crime families are planning to kill Agatha. They're worried that as a "hero," she won't allow their criminal enterprises to continue. Hadrian is horrified and launches a counter-conspiracy to kill them all and put his own lieutenants in their place, making him the king of the Mechanicsburg underworld. So far so good. The problem is that he assumes that Van, the seneschal, was one of the co-conspirators, and tried to kill him too. Why did he think that? Because Van always knows everything, which means the conspiracy could only have gone forward with his approval. Ivo notes that Van has been playing the "I am an omniscient genius" card a little too much.
Van: Hadrian... I... uh... I didn't know any of this. Hadrian:What!? Van: It's a big town... I can't know everything... Hadrian:You? Miss something like this? You? The man who used to brag: "Muahaha! Nothing shall happen in this town without my agents knowing about it!" Van: That was my Career Day essay! In fifth grade! Ivo: Hyu vos vun creepy kid.
Invincea and her friends in Invincea and the Warriors from Hell frequently get into trouble because of her inability to speak, and while a quick explanation might cool things down, it is much more common for the situation to snowball into a disaster. This has culminated in Invincea and her friends being suspected of attempted regicide, among other crimes.
In Godslave, both Blacksmiths would probably fare much better against Edith if they only bothered to explain to her just why keeping Anpu around isn't good for her. As it is, she's convinced they're morally bankrupt bad guys, and them telling her nothing beyond "he's only trouble" (something she knows already) doesn't help.
Homestuck: For most of the story, most of the characters aren't actually able to talk to each other and communicate through electronic means. The trolls and humans have completely different cultures. They are all pre-teens, an age group not known for its good judgement (though most of them are pretty bright for their age). And whenever someone does try to ask another person who knows more about the whole situation for advice, that person is usually wrong and/or trying to manipulate them. The end result is a bunch of ill-informed kids messing around with reality itself.
This becomes an issue in Kevin & Kell between Carl and Leona. When Carl decided to turn pro in gardening and leave Beige University, he wanted to keep it quiet initially. The fan speculation is that he desired to break it to Leona first, and at that time ask her to marry him. The problem is, someone leaked the news to the sports media. This resulted in Leona becoming literally the last one to know. It jeopardized their relationship to the point where Carl would ultimately return the intended engagement ring. It was only on a last-second opening of Leona's heart, urged by her father Frank, that he was finally able to straighten things out and propose to her, which she ultimately accepted.
In book 3, Mottom attempts to get her revenge on Allison for killing her husband and destroying her source of immortality. Knowing that Allison is attempting to infiltrate the domain of her fellow Demiurge and former friend Mammon, Mottom... crashes her entireFlying City into Mammon's fortress, breaching his inner vault and making all his wealth spill out of it. She then attacks Mammon because she cannot immediately see Allison anywhere inside. While a lucky break for our heroes, this doesn't really work out for Mottom.
In book 4, part of the central conflict of the book arises from Allison and 82 White Chain being unable to communicate with each other properly. This eventually leads them to have a brutal fistfight while they both scream at each other about the others' main character flaws. While they do reconcile pretty quickly and it helps in their mutual Character Development, Allison almost kills White Chain in the process and White Chain almost falls into the Path of Thorns.
In book 5, Jagganoth attempts to ask Allison for her Master Key, as it will help him fulfill his Rage Against the Heavens against Metatron (who is implied to be the Greater Scope Antagonist of the comic). Of course, because he is Jagganoth, a Shell-Shocked VeteranOmnicidal Maniac whose crappy life has convinced him life is suffering and the best thing he can do to help is to euthanizeThe Multiverse, he decides to do this while trying to kill his fellow Demiurges and immediately after having killed thousands of innocents by making an entrance. Needless to say, Allison is in very little mood to listen to him.
In this strip, Thog is questioned by a prison guard, and gives an honest and accurate account that confirms Elan's attempt to explain that he was framed by his Evil Twin brother Nale. However, Thog's statement is chock-full of homophones (and far more elaborate than his usual speech), rendering it comprehensible (with a bit of effort) to the reader but total gibberish to the guard.
In a particularly tragic example of this, Varsuuvius in the Battle of Azure City is inadvertently discovered by fleeing soldiers who stumble upon hir while invisible. They ask V to save them with V's magic, but since V fled the battle because V was out of spells, the soldiers stand around allowing the hobgoblins to catch up and slaughter them. V might have convinced them to continue running if V said "I am out of spells you fools! Flee for your lives!", though doing so might have made the hobgoblins aware of V as well. V spends the next few months in a sleep-deprived equivalent state so as not to relive that nightmare.
It gets worse: when Vaarsuvius tells V's mate Inkyrius that V made a Deal with the Devil to save V's mate and their children, and Inkyrius gets angry. V insists that Inkyrius doesn't know the whole story. Inkyrius admits this, but calls V on keeping the power V needed to save their family, and asks V to make a choice between V's power and their family. V could have tried to explain more, if only to justify why V needs (or wants) to hold on to the power a little longer, but instead V just says that V needs to make everything right again. An ultimatum had been issued and time was slipping away, but for someone who wants to keep both, V certainly isn't acting in a manner that will let V do so. Though V's mental state may be justified (for one thing, the sleep deprivation from the last entry is at its worst here).
Roy's eagerness to get resurrected and his father being a Jerkass cause him to miss a crucial piece of information — namely, the details of V's brief defection to Evil. Since V is too ashamed to tell V's friends the details either, the combination of failed and missed communication places V in exactly the position desired by the IFCC in the first place: to establish control of Girard's Gate for themselves.
Lord Shojo's death is a literal example of this trope. While in some ways, his Obfuscating Insanity and scheming served him well during his life, it comes back to bite him in the ass when the insanely overzealous Miko Miyazaki misinterprets his behavior as that of a traitor and kills him. This leads to Miko's fall from paladinhood, the fall of Azure City to Redcloak's hobgoblin army, the deaths of nearly all of the paladins of the Sapphire Guard at Xykon's hand, and the destruction of the Gate that they were guarding.
In the prequel story "Uncivil Servant" Belkar, after learning that he can make money by killing things that are causing problems for a town, decides to kill off the criminal gangs in that town, only to discover after he had killed them that they were not actually criminals gangs at all but were actually the town's police and fire departments, who were trying to recruit him for their volleyball teams and he had seen them at a Not What It Looks Like moment (soliciting donations for the teams in a way that, taken out of context, sounded like veiled extortion).
In Panthera, Onca, who is inexperienced with her transformation, and consequently has trouble speaking in it, barely manages to convey the message that they've been tricked and are fighting the good guys instead of the bad guys to Tigris. However, in an almost comedic case of You Have to Believe Me!, she fails to provide any of the evidence that led her to this conclusion, resulting in Tigris being disgusted that the villains managed to trick Onca into switching sides in a few hours. It doesn't help that Tigris views Onca as dangerously incompetent and naive.
In this strip of The Perry Bible Fellowship a kid sees a bee (as in the insect) on a vision test, causing him to get Lasik way too young for any real doctor to prescribe.
Schlock Mercenary: Lieutenant Ebbirnoth, the company's de facto Xenobiologist, spends a large chunk of Book 16 unable to speak intelligibly due to a botched resurrection. Otherwise he could have warned the others about the Essperin ability to merge with technology.
Sluggy Freelance: In "Anima", the main characters take an extended visit to an alternative dimension in which miscommunication should be impossible because everyone has a spirit-projection (anima) that shows their true emotions. They visit several different time periods because their means of travelling across dimensions is malfunctioning and forwards them in time instead. It's a Running Gag that, in spite of everything, they're almost always chased out of each time period by angry locals due to poor communication. In the "medieval" period, for example, Torg kills the so-called "King Monster", and it falls on top of the literal king of the land, killing him. Unaware of this last part, Torg declares to the baffled onlookers that yes, he meant to kill "the king" and is proud of it. They would have assumed it was an accident, but since his anima shows him to be sincere, they decide to execute him for murder. In the following time period, Torg tries to keep a secret from Zoë to prepare her a wonderful surprise, but it works horribly for their relationship because his anima keeps showing he's hiding something from her and she worries over what it is.
Sonic: The G.U.N. Project: If Shadow had been upfront with Sonic, Knuckles and Sally in the first encounter in the first issue, they could've likely stopped Commander Tower sooner. By the time he did, the three had unwittingly clued in Tower that Shadow was onto him and forced him to get involved.
This trope is what made Split Screen go: Jan went for a decade without speaking to her childhood best friend/love interest, rather than confess her feelings or confront Jeremy about his. When she does finally confess to him, she says her feelings are past tense. Jeremy, on the other hand, dodges and avoids the subject, past and present, rather than tell her how he felt, resulting in mixed messages that only fueled Jan's frustration.
Stand Still, Stay Silent: In Chapter 13, poor phrasing on both sides during a tense combat situation kept both Sigrun and Mikkel from realizing that there still was a troll under the tank, giving the thing ample time to break through the vehicle's floor before Lalli noticed its presence, and time to bite Tuuri before Lalli could take care of it.
There Must Be Happy Endings: This is something of a Central Theme. A woman is given the chance to redo the three months leading up to her husband's death. She starts speaking up for herself, and he in turn starts communicating, and it turns out their marriage wasn't as loveless as they each thought.
Trevor (2020): Invoked by Enid, as she had (most of) the messages Dr. Maddison was sending the new members of the medical team about what they were really doing to Trevor intercepted, altered, and then sent as if nothing happened, so that he would just seem like a nutjob.
Under the Oak Tree: Thanks to her abusive upbringing, Max has terrible, terrible issues speaking up for herself or voicing her desires. This causes a lot of misunderstandings with her husband Riftan. He often takes her silence or terseness for dissatisfaction with her life or marriage, when she's actually stunned by his kindness to her or afraid to tell him how she really feels.
Vixen Logic: In the beginning Red's grandpa offers her a place to stay after she loses her job, but neglects to tell her that it's a boarding house and she's going to be the new landlady. Instead she finds out after one of her tenants walks in on her in the shower and she panics. Another one of the tenants suggests that it isn't the first time the old man has done something like that, and she basically says Oh, No... Not Again! after he springs another new tenant on them later.
This happens between Ben and Alex in their middle school days. Alex constantly gets in fights to defend Ben's honour but deflects Ben's questions about it since he doesn't want Ben blaming himself for it. However, at the same time, he expects Ben to understand him even though he doesn't speak up, and resents him for not doing anything about the situation. Had the two boys communicated better, then they might not have run afoul of Donald Na.
Ben's gang nearly get into a fight with Dean when the latter mistakenly believes that they're picking on his friend Timothy. In actuality, they were just demanding a reason for why Timothy had been following them. However, Alex and Dean are too hot-headed to properly explain themselves, and instead quickly resort to violence. It's only Jake's timely arrival that stops things from getting any worse.
Welcome To Pixelton: A giant eats the protagonists, and they kill him by pressing the self-destruct button in his stomach. Unfortunately, that must have been a feature, because it turns out the giant is from a race of transporters who carry passengers in their stomachs, and he was a big fan of the protagonists who wanted them to meet his family. Oops.
xkcd: The coronavirus mRNA vaccine is given a Star Wars Poor Communication analogy: Princess Leia hands the Death Star blueprints to her officer, who then hands it off as just a blueprint for construction crew A without telling them to reverse-engineer a weakness, causing them to believe it's just more work so they offload it to construction crew B without telling them anything about the blueprints, leaving them to believe they have to build the entire thing with no oversight. They manage to create an entire Death Star to rival the Imperials' - at which point everyone other than Construction Crew B freaks out at the sudden and unexpected Death Star, and tries everything to destroy it, unaware of its origin and borderline-feral to the point they refuse communications from the passive Construction Crew B, until they finally spot a thermal exhaust port and try shooting at it, blowing up the copy Death Star and construction crew B. Then when the real Death Star shows up, they skip some of the panic with their poor-but-effective strategy of swarming the Death Star so they can hit the thermal exhaust port.
Bravely Default.