The link between measurements and accomplishment isn’t at all obvious

Moreover, measures are often accompanied by targets. And again, the implication of the target is clear: If you set a target and measure people’s progress toward it, they will, miraculously, reach that target.

But the causal connection between measurement and accomplishment is not all that obvious. After all, there are a variety of reasons why people might not—despite the measures—get it done. Or they might get something done, but not what the measurers want.

"To motivate particular individuals and specific teams, public managers have to mobilize a mix of motivators. Rarely will mere measuring be enough."

First, people may not have the operational capacity to get it done. That may mean equipment. But it also can mean knowledge. If people don’t know how to get it done, the measures will have zero impact.

Certainly, public managers ought to measure what they are trying to get done. But they also have to exercise the leadership necessary to garner the necessary resources and knowledge.

Implicit Bargain. Behind the measures and targets, public managers are offering an implicit bargain: If we give you the resources, we expect you to do it. Yet if public employees believe that those who established the measures and set the targets have failed to provide them with the necessary operational capacity—from hardware to skills, tactics and strategies—how seriously will they take their side of this deal?

Second, human motivation is complicated. Yes, measures and targets can motivate. But for any public employee, so can a lot of other things—a sense of purpose, the support and approval of colleagues and friends, recognition for a job well done.

To motivate particular individuals and specific teams, public managers have to mobilize a mix of motivators. Rarely will mere measuring be enough. To improve performance, managers need to connect the measures to important public purposes, convince employees that they can achieve both the measures and the purposes, and foster a collective and individual sense of accomplishment.

Finally, there is one additional problem in the public sector. Often, you simply cannot measure what you want done. You can measure something that is close, but usually the measure is not precisely what you want done.

For example, in K-12 education, our true purpose is clear: We want the schools to help children grow up to be productive employees and responsible citizens. Measuring the productivity of employees, let alone the responsibility of citizens, however, is very difficult. And even if we could create some good measures, we would not know how much the schools contributed. In addition, with a decades-long time lag, we could not feed back those measures to improve performance.

So we rely on test scores. That can be a useful measure. After all, children will never be productive employees or responsible citizens if they can’t add and subtract, read and write. Still, test scores are not precisely what we want the schools to get done. They are merely the best surrogate currently available.

Of course, the traditional management mantra still holds. If you measure test scores, teachers will produce test scores. We call it “teaching to the test.” That is why educators frequently observe that, “The challenge in educational testing is designing a test worth teaching to.”

Today in government, “performance management” is all the rage. Yet if you read or listen carefully, you will observe that, too often, what is meant by performance “management” is little more than performance “measurement.” And if all it takes to get something done is to measure “it,” measurement is all that is needed.

But if the public agency charged with getting “it” done is staffed by real humans, mindless measurement will accomplish little. The agency’s executive team needs to think carefully about what it wants to measure—to understand the connection between its measures and what it is trying to accomplish. The team needs to provide these humans with the operational capacity to get it done. Moreover—and this is the most complicated part—the executive team also needs to figure out how to motivate these humans.

To improve the performance of public agencies, measurement can certainly help. But performance will never go up unless the agency’s executives exercise real, motivational leadership.

Robert D. Behn is faculty chair of the executive education program Driving Government Performance: Leadership Strategies That Produce Results at Harvard’s John F. Kennedy School of Government and author of the online monthly Bob Behn’s Public Management Report.