Jakob Nielsen’s ten usability principles, published in 1994, became the standard American checklist for interface evaluation. Visibility of system status, user control, error prevention, recognition rather than recall. The list is about reducing what the user must hold in their head.
design
The kitchen machine
Die Küchenmaschine. German kitchen appliances are built with attachments that share a single drive unit, sold separately and added over years. The machine anticipates uses the buyer has not thought of yet.
Usability testing
American product development runs sessions in which ordinary users attempt tasks while being observed, and the failures are recorded as defects in the product rather than in the user. The method locates the fault in the design by default.
Hand tools
German hand tools are designed around the hand: balance point, grip diameter, the angle at which the tool sits when set down. The object anticipates how it will be held, not only what it will do.
Ergonomics
German workplace regulation specifies ergonomic requirements for seating, screens, lighting and reach, enforced through occupational safety law and inspected. The body is treated as a design constraint with numbers attached.
The Apple design principle
American consumer technology is sold on the claim that it can be used without instruction, and products are reviewed against it. A device that needs its manual read has failed a test that was applied before it shipped.
Public by default
American software companies commonly configure their internal messaging so that channels are open unless someone actively makes them private, and a private channel is something a colleague may ask about. The default is a policy. Whoever writes it has decided which way information should flow when nobody is thinking about it.
Don’t Make Me Think
Steve Krug’s 2000 book on web usability became one of the most widely read American design texts, and the title is the argument. The user should not have to work out how the thing operates.
Minimum Viable Product
Build the smallest thing that can be put in front of a real user, ship it, and learn from what happens. The word viable is doing the work. Not good, not finished — just alive enough to generate information.
The safety factor
Sicherheitsfaktor. German engineering practice works with generous safety factors, specified in DIN standards and in the professional codes of the engineering chambers. The structure is built to carry loads it will never meet. The margin is the contingency, and it sits in the design rather than in a separate plan.