Here's why:
* Nouns are words that represent people, places, things, or ideas.
* Names identify specific individuals, places, or things.
For example:
* John (person)
* London (place)
* Apple (thing)
However, it's important to note that names can sometimes function as other parts of speech depending on the context. For example:
* "John" could be an interjection, used to express surprise.
* "He's a John Doe" could be an adjective, referring to an unknown person.
But generally, a name is considered a noun.