You can’t make every worker happy, surely, and should a business even try? Evidence from our recent research suggests, actually, that the answer is yes. Or rather, our evidence shows that managers are giving up far too soon on their disgruntled employees, making them less productive than they could be, exposing their companies to unnecessary risks from thefts and leaks in the process, and inflating turnover costs.

What causes employees to become disgruntled and what can be done to prevent it? To find out we zeroed in on the most unhappy people in our data. These were 6% in our database of 160,576 employees who displayed the lowest levels of job satisfaction and commitment on their 360 evaluations of their bosses. We were looking for those among them whose managers also oversaw the most satisfied employees. In this way we identified that group of leaders who were managing both the very unhappy and the very happy at the same time.

The results of the data were clear: There is most definitely such a thing as “the boss’s favorites.” And while, in any disagreement we inevitably find both parties bear part of the fault — that is, the disgruntled employees do certainly play some role in their own unhappiness — we consistently found in the analysis that their complaints were justified. Their managers were in fact treating the disgruntled employee differently than they treated their very satisfied employees. What’s more, when the managers in question started to treat their disgruntled employees like everyone else, the employees’ behavior quickly improved.

Our results suggest a clear path forward for bringing disgruntled employees back into the fold. In particular, the unhappy group in our survey strongly agreed on six major areas in which they felt (and we agree) that their leaders needed to improve:

Encourage me more. When we asked the unhappy 6% to name the skill they thought was most important for their boss to demonstrate, the top response was “Inspire and motivate others.” Too often, managers take a negative tone with disgruntled employees. Expecting that efforts to motivate will be ignored, none are proffered, and the expectations become self-fulfilling. But our data suggest managers should take the opposite view: Work harder to inspire this group. Keep the conversation positive. Expect the best, not the worst.

Trust me more. It’s probably not surprising that both parties — unhappy employee and boss alike — distrust each other. The key to restoring trust is to operate with the belief that the other party can change. Here we’d suggest the manager make the first move by making the effort to understand the employee’s problems. Then, as both parties work on their relationship, they must strive for consistency —that is, the manager must strive to treat all employees equitably, and both parties must strive to reliably do what they say they will do. Over time, trust will grow.

Take an interest in my development. If a person works hard and gets a pay check he has a job. But if a person works hard, gets a pay check, and learns a new skill, she has a career. Career development should not be focused only on the high-potentials. As counterintuitive as it may seem, don’t leave the underachievers out when distributing stretch assignments.

Keep me in the loop. Communication is fundamentally a management function, so this responsibility rests squarely with the managers. Great communicators do three things well. First, they share information and keep everyone well informed. Second, they ask good questions, inviting the opinions and views from others — all others. Third, they listen. And not just to the people they like.

Be more honest with me. People want to know how they’re really doing on the job — and the one’s not in favor perhaps even more than the one’s feeling the warm glow of approval. They want to know why they’re falling short. They want a chance to improve. Too often, though, the bottom 6% felt their bosses were not giving honest feedback, glossing over problems with comments like “You’re coming along fine,” when clearly they were not. What’s more, many reported promises being made (“if you finish this project on time then…”) that were not kept. Honesty is the bedrock of good relationships.

Connect with me more. Anything managers can to do improve their relationship with the disgruntled employees will have a significant positive influence. Here’s where favoritism takes on its most concrete form: managers go to lunch more with people they like, our data show; they talk with them more socially (about children, sports, etc); they know them more personally. This is natural, surely, but so are the feelings of exclusion it creates among the less favored. A small effort by managers to spread their attention around more broadly can go a long way here.

As leaders, our knee-jerk reaction to unfavored (and disgruntled) employees is often — “It’s their own fault!” Our research shows this is not always (and often not wholly) the case. Before you settle for letting your dissatisfied people go and cost your organization thousands of dollars in employee turnover, take a moment to consider how these performers need to be treated.

If not for their sake, then for everyone else’s sake. Research by the University of British Columbiarecently published in the Journal of Human Resources has shown that those who witness workplace bullying become equally disgruntled as the victims and just as likely to quit. All employees need leaders who know how to inspire and motivate them, give them opportunities for development, and treat them with the respect and dignity they each deserve.

A third of a person’s life is spent in the workplace, sometimes more. When the environment is created by an extraordinary leader who cares about everyone’s development, it leaves employees with little room to complain.

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