Why does it feel negative (for some) to be called predictable?

Sometimes I get to be called predictable, by my girlfriend for example, when I make a joke or act a certain way.
For a reason, although it is said in a lighthearted way, I feel a bit put down…, feel it as a negative qualification.
Tonight, on a tv show, someone was called predictable as well, and the host said to that person “what a terrible thought, he?”.
So I wonder; what is it that some people feel it as a negative thing to be called predictable?