Here's why:
* "Special" is an absolute adjective: It describes a quality that is unique or exceptional, not something that can be more or less than "special."
* We use other words to express degrees of specialness: If we want to express different levels of specialness, we can use words like "more unique," "very important," "extremely valuable," etc.
Let me know if you'd like to explore other words that express degrees of uniqueness or importance!