Germans and Japanese perform engineering on every single component of a machine. Therefore, everything will succeed and fail in an exact way as predicted. Despite all the detail, German cars fail more often. This is not because they are not appropriately engineered but because Germans love rules, they follow their rules, and just like that, they expect everyone else to follow the rules as well. On the other hand, when a Japanese design a product, they ask themselves the question that how their customer is going to use it and what can they do to prevent the failure of their cars or products.
For this matter, anyone who uses German products has to use them exactly the way the German manual tells them to use it. If the user goes outside of those limits, the product is bound to fail. Japanese products take a nice beating outside the specifications and still work for a more extended period. A team of chemists, fluid dynamics engineer, and material engineers developed a particular filter which was designed for specific water treatment. It was created in such a way that it was able to accommodate nearly 75% of industrial clients and gave a precise specification sheet which dictated the working conditions.
A month later, a sample came into the lab with water which was purple and another one with clear water. It was explained that the filter turned the water purple and hence, it was a failure. When the clear water sample was examined, it showed 2% more manganese content. This caused the water to precipitate as KMnO4. The samples were declared imbecile and were sent back to the customer with a recommendation. There is no doubt that both Germans and Japanese are masters of creating the best products in the market, however, if you want your product to last longer while going outside the manual, made in Japan would perhaps be a better choice.