Design implies a conscious effort to create something that is both functional and aesthetically pleasing. This person's job is to communicate the message and to make it look good. The first step in the design process is the identification, classification and selection of constraints. The process of design then proceeds from here by manipulating design variables so as to satisfy the non-negotiable constraints and optimizing those which are negotiable. It is possible for a set of non-negotiable constraints to be in conflict resulting in a design with no solution; in this case the non-negotiable constraints must be revised. For example, take the design of a chair. A chair must support a certain weight to be useful, and this is a non-negotiable constraint. The cost of producing the chair might be another. The choice of materials and the aesthetic qualities of the chair might be negotiable. - Wikipedia
Even when designing for oneself, there are always non-negotiable constraints.
