Even for the biggest fans, anime can oftentimes be confusing, so it stands to reason that non-anime fans can be totally lost when it comes to some of the genre's more bizarre tropes. Why do anime dudes have so many nosebleeds? Why don't the Japanese characters "look Japanese"? Why do characters always scream when they are doing a special move? Believe it or not, many of these oddities actually have explanations. Some seemingly random cliches have roots in Japanese culture, while others are more specific to the anime industry. Whether you're a non-fan, a casual viewer, or a total expert, there are probably some pieces of anime logic that you've never been able to wrap your head around.
There are a surprising number of anime characters who don't look their age. While it's not always as drastic as a 40-year-old woman who looks like a young girl (sorry, Kinue), more mild examples can still be jarring. While this trope appears frequently in anime, there's no established explanation for it.
In some cases, the choice may be somewhat insidious. If a super young looking character is really an old person, it's less morally reprehensible sexualize them. Even if your eyes signal that something is predatory, official canon can step in and say "no, really, this character is an adult." Otherwise, it might just help to differentiate one character from another, and sometimes the discontinuity is explained in the plot.
In real life, people get nosebleeds for reasons that include dry air, allergies, and other causes that have nothing to do with being turned on. In anime, nosebleeds have a more lustful cause, as they're a visual stand-in for a feeling of arousal. This isn't completely illogical, as arousal does involve increased blood flow, just not to the nose.
However, strict Japanese censorship laws make it hard for anime characters to talk openly about feeling aroused, so anime studios get their point across via fountains of hemoglobin.
Some of the weirdest hairstyles ever conceived are featured in anime, and it can be baffling for both non-fans and those who are well-versed in the style. The reason why some character's hair resembles a robotic crab hood ornament all comes down to marketing.
When characters have bizarre hair, it creates a silhouette that distinguishes them from others in the series, and it also helps make the franchise instantly recognizable. This makes it easier to create merchandise, and solidifies brand recognition.
If you've seen Dragon Ball Z, Naruto, or basically any anime that involves fight scenes, then you've heard characters loudly announcing their moves. This happens so often that most anime fans don't even question it, but for non-fans, it can be a little strange. This oddity is actually a byproduct of adapting manga series into anime. When depicted in static, written form, it can be hard to tell who is attacking who, so shouted moves make it way easier to follow the action. This isn't as necessary in anime, but the tradition carried over anyway.
Characters also repeatedly announce their names, as well as the names of the people around them, to the point where it can seem absurd. This actually goes back to samurai culture, which emphasized individual, honorable battles. If one's opponent was renound, defeating them yielded more honor, so knowing exactly who you were fighting made a huge difference.
For this reason, duels often began with the duelists announcing themselves, and that tradition is lovingly recreated in many anime.