Negotiation improves when ego stops treating compromise as defeat.

Once compromise starts feeling like losing, the negotiation stops being about the outcome and starts being about the self. People then hold positions that cost them real money to avoid a feeling that would have passed in an hour. The ego makes bad trades and defends them well. Recognizing when it has entered the room is most of the fix.

When you feel resistance to conceding a point, ask whether you are protecting the result or the sense of having held. If it is the second, give the point and watch what happens. The relief and the improved terms usually arrive together.