He was following the tenth principle: Good design is as little design as possible.
Rams' design philosophy centers around the idea that good design should be simple, intuitive, and focused on the essential functions of a product. He argues that designers should strive to create products that are "less, but better" – fewer features, fewer materials, and fewer distractions, but with a higher level of quality and attention to detail. He was following the tenth principle: Good design
To avoid "pdf pdf pdf" concatenation errors again: but better" – fewer features