Why don´t engineers write performance specifications?

This paper discusses two reasons why engineers may be reluctant to specify products strictly in terms of performance. The first is a consequence of responsibility for the implied warranty that accompanies engineering specifications. Even though only a functional description of the product may be needed in the specifications, this responsibility necessitates detailed knowledge of applicable designs to ensure that the set of performance requirements specified can actually be met. The second reason is based on the length constraint for such documents, and a simple method is suggested for preventing difficulties that may result from that constraint