Why: Design reviews should demonstrate by calculation or through the use of models and reliability tools that the system is capable of achieving the design objects rather than making a giant leap of faith that all will be well and good.
When: Design reviews for reliability should be a part of the design process starting with conceptual designs and ending when the drawings are revised for the as-built system.
Where: This is a logical extension of the design process to show me rather than tell me how the system will function and is performed as a portion of the up-front design by the numbers process.
These definitions are written by H. Paul Barringer and are also posted on his web site at www.barringer1.com