Good design makes a product understandable—Rams' 4th principle

Dieter Rams' "10 Principles of Good Design," Principle 4: "Good design makes a product understandable (Gutes Design macht ein Produkt verständlich)." Vitsœ's official description elaborates with a beautiful three-stage explanation:
"It clarifies the product’s structure. Better still, it can make the product talk. At best, it is self-explanatory."
Rams aimed for products that didn't require an instruction manual—designs where the product itself communicated. This concept is similar to the "affordances" or "signifiers" in modern UI/UX.

What does it mean for a product to "talk"?

The choice of the verb "talk" is intentional. Rams aimed for designs where objects autonomously communicated their intent, rather than designers instructing users. His methods were concrete:
Form indicates function: The tuning dial on the T3 pocket radio (1958) has ridges, conveying the non-verbal instruction "touch and turn." Color is used only as a signal: On the ET44 calculator (1977), basic colors were black and gray, with only the "=" button highlighted in yellow. This design communicates "press this last" with a single color. The color scheme of the ET44 was almost directly inherited by Apple's original iPhone calculator app.
And the visualization of structure: The transparent acrylic lid of the SK4 record player (1956) immediately conveys "this is a machine for playing records" by revealing the internal turntable. The transparent lid serves as a substitute for an instruction manual.

Resonance and Differences with Don Norman

From the same problem awareness that led Rams to formulate Principle 4, design researcher Don Norman proposed the concept of "affordance" in his 1988 book "The Design of Everyday Things." "How can a product communicate how it should be used?"—this question shares the same roots as Rams'.
Norman later evolved from "perceived affordances" to the concept of "signifiers." A signifier is "any perceivable clue that communicates to the user how an object can be used." Rams' "product talking" is precisely the function of a signifier. The ridges on the T3 radio's dial were a signifier implemented 30 years before 1988.
However, there are also differences between the two. In later years, Norman pointed out the danger that extreme minimalism "removes cues for operation." Even if a surface is beautifully organized, if the presence of an operation is not visible, Principle 4 has not been achieved—this criticism also serves as a warning for modern app design.

"Talking" Design in the Bathroom

Bathroom accessories are one of the categories where Principle 4 functions most naturally. In hotels or rental properties, products and instruction manuals are not provided together. In an environment where hands are often wet, it's essential for the design to immediately convey "where to hang a towel" or "how to get soap."
ZACK's magnetic soap holder is a modern embodiment of this principle. The small silver circular disk on the soap holder acts as a signifier, saying "place soap here." The soap sticks by magnet—it falls when pulled off—and then one realizes it's magnetic. This sequence of experience itself is the implementation of "the product talks." Without an instruction manual, the form and material communicate its use.
Next time, we will explore Principle 5, "Good design is unobtrusive."