A moment of anger can be quite involuntary. Something happens, crashing against our expectations of how things should be, and all of a sudden, we are furious.
Okay. But then what happens.
Choosing to fan the fury leads to barricading oneself on a self-righteous patch of moral high ground. Not a fun or productive place to live. This approach keeps us from being able to listen and relate to people who think differently from us. And so, anger keeps us from seeing and responding effectively to the situation that made us angry in the first place.
If we find ourselves to be furious, we can afterwards choose to become curious.