The point at which a process or thing, especially a state of mind or emotion, reaches its greatest strength and remains steadfast; sticking-place
I could not screw my courage to the sticking point.
A disputed issue or state of affairs that causes an interruption or outright impasse in progress towards some goal or resolution, especially in negotiation or argumentation
A major sticking point had arisen over draft article IV of the proposed treaty dealing with the disputed Antarctic claims and rights.
A sticking point in a discussion or series of negotiations is a point on which the people involved cannot agree and which may delay or stop the talks. A sticking point is also one aspect of a problem which you have trouble dealing with. The main sticking point was the question of taxes. A point, issue, or situation that causes or is likely to cause an impasse. something that a group of people cannot agree on and that stops them from making progress
knackpunkt (kontroverser punkt ohne aussicht auf einigung)