Final answer:
In engineering, the decision to design parts that can be purchased off the shelf depends on various factors such as cost-effectiveness and customization.
Step-by-step explanation:
In engineering, whether or not to design parts that can be purchased off the shelf depends on various factors. Parts that can be purchased off the shelf are often more cost-effective and readily available, which can save time and resources. However, designing certain parts can allow for customization and improved functionality. It ultimately comes down to the specific requirements of the product being developed.