As business leaders, we often worry about former employees badmouthing their business or even stealing from the company on their way out the door, but those aren’t the people who pose the greatest risk. The workers who can really bring your business down still work for you.

In case you haven’t heard, there’s an engagement crisis in the workplace these days. Research cited in Gallupindicates that as many as 60 percent of workers are not engaged at work, representing more than $600 billion of lost productivity per year. 

It stands to reason people who don’t like what they’re doing won’t do very good work. That’s why I think the most damaging people at a company aren’t the ones who quit and leave.

They are the ones who quit and stay. This is the situation where the employee says, “I hate it here. I’m leaving as soon as I find a decent job, but I’m not going to say anything until I give two weeks’ notice.” They’re physically present but mentally long gone.

When it comes to employee engagement, ignorance isn’t bliss. Just because someone is physically in the office doesn’t mean everything is going well.

That person could be letting key tasks slide, quietly missing deadlines or even putting key client relationships at risk. People who are unhappy but trapped are often the ones who damage morale by complaining and spreading rumors, copying intellectual property and creating a toxic environment. And they do this from the inside, which is far more damaging than the average rumor spread by an ex-employee.

Why do they behave this way?

Many employees are afraid to speak honestly about challenges and problems at work, even those that might be solvable. They fear that if they approach their managers and say, “Hey, I don’t know if this job is working out,” they’ll be told to pack their bags. That’s a terrifying situation, especially where they have a family to feed and bills to pay.

Understandably, they avoid honesty–or full-out lie–right up until the day they quit. At that point, you suddenly have a new hole to fill.

Bad departures leave bad feelings on both sides that can overwrite years of goodwill and great work. Here are four ways to get ahead of this issue and keep unhappy employees from becoming toxic:

1. Measure engagement and ask for feedback.

At my company, Acceleration Partners, we regularly ask employees if they’re present and engaged. We use Tiny Pulse to send out questions each week to gauge how employees are feeling about work. We also spend time at our annual retreat discussing what the company should start, stop and continue doing.

2. Act on that feedback.

When employees make good suggestions, implement those changes. Be open-minded about criticism, because your employees may be able to see emerging problems from the front lines before they are clear to you. Engagement cannot be a one-way street.

3. Create a safe culture.

If you want people to be honest, you cannot walk them to the door for speaking their minds, you have to create a safe space for honest dialog. You need to hear what they have to say, see if it’s a problem that can be solved, and work out a plan together.

Maybe you will find the person would fit better in another role. Maybe the person is overworked or under-challenged.

Sometimes, adjustments can be made. Even if they can’t, it’s better to talk things out. Otherwise, problems fester and employees mentally check out.

4. Make it okay to leave.

A particular worker might not be a great fit for your company anymore. That doesn’t mean he or she won’t be an asset elsewhere, so make the parting a win-win process.

At McKinsey and Company, a global management consulting firm, when people want to leave, the company provides resources to help them transition out. Since employees who leave the company often go on to work for potential clients, the company has taken the long view and created an alumni association. They don’t want to unnecessarily burn bridges.

People are going to leave your company. Even at companies listed among the best places to work, the average employee is only on the job for 24 to 32 months, according to Paysa research. 

People change, their interests change, companies change. It’s simply inevitable that people will move on.

So, rather than burying your head in the sand, prepare your workers and your business for the inevitable transition. It’s the best way to prevent people from quitting the job and staying on your payroll.

Originally published on LinkedIn.

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