Get Rid of Guessing GROG
My friend, Clark has a saying that he relies on, and it works. Get Rid of Guessing! I have been involved in too many product development projects where too many variables in the design are too little understood. Assumptions on the state of interfaces between two tiny components, guessing essentially. They didn't KNOW with precision how the interaction would perform under even a narrow range of circumstances. They were guessing that everything was fine, and in a complex product design, guessing leads to failures. Failures that happen in the later stages, even in the V&V phase cost MANY TIMES more resources to correct. Hence, get rid of guessing. Do the math, systematically calculate down the the smallest level needed in order to know how your product, its subsystems, and it's components will react under all the conditions that you product could experience in the actual world.