Deadlock is many negotiators’ worst nightmare. It happens where there may well be a deal to be done but neither side seems willing to move towards the other in order to bridge their differences. If you are not used to this, it can be psychologically very uncomfortable.
In fact, creating deadlock on purpose is a key part of the armoury of hard-ball negotiators. They do it to make sure they have drained every last drop of advantage for themselves before agreeing any deal. And, because they do this habitually, they are often very good at it. For them, there is no apparent concern at all about being stuck in impasse. They are only waiting for you to blink first.