When you don't want to switch into new opportunities.
Did they offered you a new job ?
Yes, but I'm good where I'm good.
The ultimate expression of condescension, usually it's employed when someone is too cowardly to turn something down directly. It essentially means "No." or "I must decline.", but it sounds wishy-washy and weak. It's used so much because it's way easier than saying "No." and it also for some unknown reason sounds more polite and less blunt.
Guy: Hey do you wanna go out to the restaurant with me?
Woman: (Staring into her phone) Ummmm no thanks I'm good.
When you tell Cady Heron that Regina George is cheating on Aaron Samuels with Shane Oman in the auditorium above the projection room. "And that little one is Gretchen Wieners."
But I never told anybody that because I'm SUCH a good friend.