Final answer:
The paramount design objective for the I/O facility, alongside generality, is efficiency, which involves optimizing resource usage and maximizing throughput.
Step-by-step explanation:
When considering the design of I/O (Input/Output) facilities in computing, two primary objectives must be achieved for a robust system: generality and efficiency. Generality refers to the system's ability to handle a wide range of devices and types of I/O operations in a consistent manner. Efficiency, on the other hand, is concerned with minimizing resource usage, such as CPU time and memory, and maximizing throughput, which means the system can perform a larger number of I/O operations in a given amount of time.
An I/O system designed with efficiency in mind ensures that the devices are able to perform at their optimal speed and that the software overhead is as low as possible. It involves strategies such as buffering, direct memory access (DMA), and interrupt-driven I/O to make the best use of system resources. Every I/O operation can impact the overall performance of a computer system; hence, optimizing for efficiency is essential.