Checking Up

Do bosses have to know how to do their people's jobs in order to be able to check and ensure they're being performed correctly?

I remember having a discussion with one of my team leaders about spot-checking the work of our teams. He was adamant that a boss needed to know exactly how to perform his people's work in order to accurately determine if the work was being performed and performed correctly.

I disagreed with him. I said that key indicators often let a boss know whether work was being performed. Sure, the quality of the end result or product will let bosses know 100% (more traditional key indicators), but then it's too late to make any corrections. Let's face it, bosses are supervisors, not worker bees, and it's often not possible to realistically know how to perform every step of every team member's job.

I gave the team leader my example of ensuring that maintenance was being performed on a fleet of trucks. I said that, while I didn't know how to perform all the preventive maintenance, checks, and services on the trucks, I could check the tire pressure, the cleanliness of the oil dipstick handle (it was very large and easily got dirty), and battery cell levels to get a decent idea if the maintenance was being performed. I believe I convinced him of my argument.

What do you think? Are there checks that bosses can perform that allow them to see their teams' work is being done? What examples do you have?