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.
Americans expect initial parts of a deliverable as quickly as possible. A partial deliverable early often meets the needs better than the complete product on time. The remaining parts of the deliverable are then supplied promptly. Speed is preferred to completeness.
Germans are impressed with American rapid response times. But often they misperceive the initial deliverable as most or all of what they will receive. They then falsely conclude that their American colleague has not fulfilled the agreement.
To then learn that they need to aggregate several parts of the deliverable leads them to the conclusion that their American partners are either incapable of or unwilling to deliver a complete product.
There are few situations in the U.S. context in which missing a due date is easily justified. From the American point of view, German colleagues are simply too slow, their deliverables are too complete. Opportunities are missed.
Particularly frustrating is to have very little communication during the time span of the agreement. And then suddenly, and without warning, the deliverable arrives.
Advice to Germans and Americans
Completeness vs. schedule, quality vs. speed, whatever terms you choose, this is an area of potentially considerable friction. Address this issue from the very outset of an agreement. Define the terms specifically:
What deliverables are involved? In what form will they be delivered? In pieces or as a whole? By when? From whom and to whom? For the sake of clarity, recommend to each other that you document this. And most importanlty, remain in constant contact (follow-up) with each other about any modifications to this crucial part of the agreement.