There will be one lightest design, one stiffest design, and an infinite number of designs that are some compromise of weight and stiffness.

• 因为这两个目标的冲突，权衡存在。将有一个最轻的设计，一个过硬的设计，以及无限的设计，有一些妥协的质量和刚度。这套权衡设计被称为帕累托集。