A tactic that Iran seems to have used several times in the negotiations over prisoners and, if I recall correctly, the nuclear negotiations, is to get close to an understanding and then say, nope, we’re going to insist on our original position. Then they backtrack when faced with a nope on the other side. From the information available, it’s not clear whether this happens because too many people have a say in the negotiations or because Iran thinks it’s a useful tactic. It seems not to have gotten them much and nearly wrecked the negotiations a number of times. If it’s a tactic, after it’s been used a few times, the other side can recognize it and respond accordingly. One of those continuing mysteries. More here.