From the German perspective a product should never break down. It should be 100% reliable. Not only the German engineer thinks this, but also the German consumer. Germans are perfectionists. A reliable product, like a reliable person, delivers on it promise.
For Americans a reliable product functions well under adverse conditions. If it has problems, the supplier reacts promptly with good service, at minimum additional cost via the warranty, and at minimum inconvenience by offering a replacement product.
Germans pride themselves on their technical prowess. An unreliable product of their own making is a reason for embarrassment. An unreliable product of another‘s making is unacceptable. Germans find American products to be less reliable.
Americans tolerate less reliability as long as it is compensated by good service and fast response time. In fact, a technically more reliable product can be more problematic if its service contract and its service provider are unresponsive and/or expensive. Reliability is just one among several product characteristics.
Advice to Germans and Americans
Enter into and remain in dialogue about how you define reliability: what are the market demands, where is your competition, how you can meet, possibly surpass the market and the competition?