Here's why:
* Japanese language has many sources: Japanese has been heavily influenced by Chinese, but also has native words and words from other languages like Korean and English.
* Words can have complex histories: A word might have originated in Chinese, but then evolved differently in Japanese. Some might have been borrowed directly, while others were adapted and changed.
To get a proper answer, please provide the specific Japanese word you're curious about.
For example, you could ask:
* "Where did the Japanese word 'sushi' originate?"
* "Did the Japanese word 'kawaii' come from Chinese?"
Once you provide the word, I can tell you its origin and how it came to be part of the Japanese language.