The usual reasons
Why my Chinese name sounds fake
Natives are not guessing your personality. They are reading grammar. Fake, here, means: this string was built as a pronunciation key, a caption, or a pretty-girl sticker — not as 姓 + 名.
It has no surname
A Chinese personal name starts with a family name from a real list — 李, 王, 张, 陆, 费 — then a given name of one or two characters. 约翰, 玛丽, 莎拉 skip that step. They are two foreign syllables in a trench coat.
It is the dictionary row for your English name
If every Sarah in the class is 莎拉, the name is a look-up, not a naming. The Xinhua transliteration table exists so newscasters can say foreign names. Teachers borrow it because it is fast. Fast is how you get a generation of Kevins named 凯文 instead of something with a 姓.
It collides with food, mascots, or captions
莎拉 sits next to 沙拉 (salad). 山姆 is Sam and Shamu. 好天使 is a choir caption. None of these are insults aimed at you. They are what happens when a naming system optimizes for sound or vibe.
It wears a pretty-girl suffix as the whole identity
娜, 莉, and 丽 appear in real names. When they are the only signal — a thin given name ending in 娜 because a teacher wanted “feminine” — natives hear the assignment, not the person. That is a Fix, not a character assassination.
It is too long, or it wants a middle dot
Ordinary modern Han names are two or three characters. Five-character Olivias (奥丽维姬) and news-wire strings with 间隔号 · (罗莎蒙德·派克) are how foreign names are filed. See the attested fails.
Fake is not the same as offensive
Most textbook names are not slurs. They are just not names. If a string is actually a dirty homophone, the checker will say so as a specific Kill. We do not call your name “weird” as a personality reading. We say whether a native would use it.