FORTUNE — Trouble meeting deadlines, ignoring requests or instructions, hogging the limelight in staff meetings — anyone who manages other people probably has at least a few underlings whose work, while okay (or even excellent) overall, could stand to improve in some particular way. As a boss, you may even have told them so repeatedly. Yet nothing changes.
“Nearly two out of three employees say they’ve received negative feedback” in performance appraisals, says a new study by Joseph Grenny and other co-authors of a book called Change Anything: The New Science of Personal Success. The research found “managers giving employees the same negative feedback year after year with little effect on performance.” Only about one-third of those who have been asked to shape up have shown any noticeable improvement.
What gives? “Our whole idea of how to motivate people is outdated,” says Grenny. “The underlying assumption in most performance reviews is that, if you just tell people what’s wrong with them, they’ll feel badly enough to go and do something about it. The trouble is, we now have 40 or 50 years of research showing that it doesn’t work.”
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That’s not to say that motivating people to change their ways doesn’t help. It does. But it seems motivation alone isn’t enough. Grenny’s study found that employees often “lack the ability to put their performance feedback into action.” Among those who had received negative comments in a review, a whopping 87% said they left their bosses’ office without a specific plan for fixing what was wrong, and that’s why nothing happens. In the immortal words of Yogi Berra, “If you don’t know where you’re going … you might not get there.”
Grenny says part of a manager’s job is to help employees make a road map for improvement. He suggests doing it in these four steps:
1. Explain why change is needed. “Describe … why you need the behavior to change, including its effect on other people in the organization,” says Grenny. Just saying, “Stop [or start] doing this” is far less meaningful to most people than conveying a clear picture of exactly why it matters.
2. Start a dialogue. “Usually, employees control some aspects of whatever the problem is, but not others,” Grenny notes. “So you need to have a problem-solving talk. It needs to be a real conversation,” defined as one where you ask questions and listen carefully to the answers.
“Does the person lack the skills to do what you expect him to do? Is there a lack of resources? Are there disincentives to change that you might not know about?” asks Grenny. “Unless you get to the bottom of what is really happening with this employee, there will probably be no change.”
Feeling brave? You might also ask whether you are perceived as standing in the way, he adds: “About half the employees we surveyed said their bosses were actually preventing them from performing better by, for example, not giving them clear direction, or by piling on unrealistic demands.”
3. Come up with a plan. Based on what comes out of this discussion, Grenny says, “arrive at some practical, specific ways of addressing the problem.”
4. Set short-term goals. “You want to try out possible solutions for 30 or 60 days, not six months or a year,” he advises. “It’s a way of testing whether you’ve pinpointed … the difficulty.” If there’s still no progress after a month or two, meet with the employee again to discuss why that’s the case.
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Of course, old habits are tough to break and, if you’re the one on the receiving end of a negative review, no matter how helpful your boss is, you still need to do most of the heavy lifting on your own. Need a way to keep yourself on track? “Visualize your default future,” Grenny suggests. “Motivate yourself to change by mentally visiting the career you’ll be stuck with if you’re repeatedly passed up for promotion.”
