Good design is honest.
We designers, we don't work in a vacuum. We need business people. We are not the fine artists we are often confused with.
Good design makes a product understandable.
Good design emphasises the usefulness of a product whilst disregarding anything that could possibly detract from it.
Question everything generally thought to be obvious.
An honest design communicates solely the functions and values it offers. It does not attempt to manipulate buyers and users with promises it cannot keep.