Here's why:
* Implies pressure: Pushy people often try to force their will or opinions on others, making the recipient feel pressured or uncomfortable.
* Lack of consideration: Being pushy often means ignoring the needs or feelings of others.
* Aggressive behavior: The word itself suggests a forceful, sometimes even aggressive, approach.
While some might use "pushy" in a neutral sense to describe someone who is determined or ambitious, its primary meaning is negative and carries connotations of disrespect and rudeness.