The negotiation that cracks first, twice, has a pattern problem.

A concession is something one side gives up in a negotiation to keep the deal moving, and it only works when there is a limit behind it. The occupation date is a common place to see this go wrong. A buyer agrees to move in later than planned, and a week later, when the seller asks for more time, agrees to push the date again. Each step looked small. Together they show that the buyer never decided, before talks began, what date was actually livable.

That is the pattern problem. Someone who cracks once may simply have misjudged a point. Someone who cracks on the same point twice is negotiating without a floor, so every new request becomes a fresh decision made under pressure. The other side learns this quickly. Once a seller sees that the date moves when pushed, the light fittings and the pool pump are next.

The limits get set away from the table. Before an offer goes in, a buyer can work out the latest occupation date they can manage, given the notice period on their lease and the cost of moving twice, and which fixtures must stay. Written down, those limits stop being feelings and become positions. None of the concessions felt like losing on the day it was made.