Design philosophy and goals

Engineering criteria are frequently expressed in terms of these principles  

Safe—Does not cause accidental damage to people or property. Effective— Achieves the design objectives fully. 

Efficient— Minimizes expenditure of resources versus benefits. Cost-effective—First cost and annual expenses are either commensurate with the goals or provide an acceptable rate of return on investment. 

Reliable—Minimizes downtime due to malfunction, damage, or environmental conditions. 

Robust—Handles design events that exceed design conditions without catastrophic failure. 

---