Please don't let an invitation be your introduction to me. If I haven't talked to you, haven't had some kind of discussion with you, your invitation to join your FC / Linkshell / Party is unwelcome.

I find Party invitations to be particularly unwelcome. They pop up, stop me from doing my fighting against the mob o' the moment until I deal with them. The answer is always negative, but it stops me from fighting effectively for several seconds. And if I turn down your party invitation, and you invite me again? You've just become a jerk, in my book.