A candle is a rectangle when seen from the side, a circle when seen from above (or below), and a pinprick of light when seen in the dark.
Stories, like candles, depend on our point of view. Let me sketch a comparatively tame example. Setting: student A taking oral exam in history with Professor B.
Point of view A: Did I hear him right? I’m shaking, shambling through the narrative, yup, aaaand said that name wrong, I’ve got sweat patches on my white shirt, I should have worn dark. The professor, he keeps piercing me with that look telling me I’m going to fail, and now he’s writing something down, probably the year I just got wrong, and the battle I just misplaced, he’s counting my mistakes, disaster, disaster, disaster.
Point of view B: Aha, correct, fine, right, God this is boring, why does she keep playing with that earring, she’s already got droopy ears, now she’s tapping her foot, chewing gum between questions, and she just checked the time on her phone, again. I’m as bored as her, I gave her maximal marks the moment she opened her mouth because we both know she’s learned the book by heart, but there’s the protocol, I have to ask another question after this, tralala, let me doodle a Snoopy for a while to pass the time.
Who’s right?
A first person narrative is an intimate experience, the closest to living someone else’s life, but it suffers from the same limitations as living your own life: it’s a blinkered perspective, prone to bias. There is no right or wrong.

The inability to see beyond ourselves to the “objective reality” can lead to a severe disparity of viewpoints. This is the so-called Rashomon effect, named after Rashomon, a film by Kurosawa from the 1950-s, where murder witnesses give contradictory statements.
Unsurprisingly, conflicts are rooted in the Rashomon effect—as are most good novels.
In mainstream fiction, truth and thoughts are fickle, highly sought-after commodities that are usually hidden by the conniving author. Indeed, most misunderstandings have to be inferred by the reader or by the characters, and only occasionally is the book’s “objective reality” made explicit in a Watson-Holmes type of interaction.
But wait, objective reality is boring; don’t you wonder what it’s like to be someone else?
Whilst in real life you can’t actually walk a mile in someone else’s shoes, or see the world through their eyes, in a book, however, you can. Remember Grimm’s Snow White? Young beautiful girl put by evil stepmother into comatose state after swallowing poisonous apple until rescued by prince? The stepmother (I’ll call her Queen) is so evil she orders a huntsman to murder the stepdaughter (I’ll call her Princess) and bring back her heart or lungs or liver, depending on which version you read, to be eaten by the Queen.
That was so 19th century.
Steps in Neil Gaiman with Snow, Glass, Apples in 1994. His short story is a retelling of Snow White—it keeps all the well-known elements of the fairy tale —but it’s written in the ultimately biased viewpoint: in first person, from the Queen’s perspective. (Far from the omniscient narrator of fairy tales.)
Quote: And some say (but it is her lie, not mine) that I was given the heart, and that I ate it. Lies and half-truths fall like snow, covering the things that I remember, the things I saw. A landscape, unrecognisable after a snowfall; that is what she has made of my life.