Interview candidates must be familiar with one or more key business processes such as Manufacturing, Production, Service, Sales Operations, Customer Service, Hiring, Talent Management, etc. Every department in a business has key business processes.
Show the subject a basic diagram illustration like the one attached (I created it using SmartArt in PowerPoint). and then ask her/him to describe a diagram of a key process they are knowledgeable about. Put that into your paper.
Identify any bottle necks in the process.
Ask what is the maximum capacity for the process. Does it change during different business seasons, i.e., do they ramp up for a holiday season? Make sure you describe the capacity in all relevant terms such as "Orders per hour" or "Revenue per month," or "Customers seated per hour. Keep in mind if they measure in terms of "Customers per hour," they also track "Revenue per hour," "Orders per hour," and other things, all at the same time.
Ask what is the typical or average output for the process.
Ask why the average output is different than the maximum possible capacity.
Ask if there have been process improvement efforts in the past. Get details, ask how it's changed, how it's better, what is the savings/gain, etc.
Ask if there were ever process improvement efforts that did not work - and they had to return to the original. Get details about what did not work.
Ask if there is flexibility in the process, parallel processes, or if there are times when another department or work station has a significant impact on the key process.