Performance is a function of likability. Like it or not.
If you want to get a great deal done, you will have a better shot if people like you. When people like you, they say nice things about you, they will do favors for you if asked, and they are pleasant and friendly towards you. If you are liked, your name is spoken favorably in reviews and as promotions and other opportunities are discussed.
So then the question becomes, how do you ensure that people like you?
Here's the kicker. People like people who are self-assured, willing to be vulnerable, and kind. People like people who like themselves.
Want a jump on performance? Learn to like you.