A yes in the German context is more exception than the rule. Germans are reluctant to enter into an agreement without being sure that they can deliver. They, therefore, respond almost instinctively with reasons why they cannot (yet) enter into an agreement.
For the German yes signals a high degree of commitment. It is the equivalent of giving your word, of entering into an oral contract, something not done without first giving the agreement serious consideration.
The German no is more the rule than the exception. However, its level of hardness is based on contextual factors. It can range from a hard to a flexible no. Only through asking what the barriers are to the yes is it possible to discern how hard the German no actually is.
And converting a German no into a German yes means identifying, addressing, and overcoming the reasons for the no. This can require a lot of time and effort. But as stated before, the German yes is worth fighting for.
Because the German yes involves a high degree of commitment, before granting it Germans request a lot of background information. For three reasons:
First, it helps them to determine whether the agreement could have negative effects on them, their work or their team. Second, if they say yes, they want to fulfill their part of the agreement.
Third, because Germans do little to no follow-up during the time-span of the agreement, the better they understand the overall context, the better they can fulfill their commitment. The term is front-loading.
In Germany follow-up is infrequent. Once an agreement has been made neither party feels the need to contact the other in order to inquire about the status or priority of that agreement. Agreed is agreed.
And agreements are meant to be held. The priority of an agreement remains at the level it was assigned when entered into. There should be no need to verify or reinforce the importance of an agreement.
The Germans prefer a complete deliverable, even if late, over an incomplete deliverable, on time or even early. Lateness is tolerated as long as expectations are met. Completeness is preferred to speed.