“Engaged employees are happy employees,” someone recently had the misfortune of saying in front of me at a meeting. Why does this seemingly harmless statement make my ears ring and my mouth twitch?

Because it’s not true. Even when you get a great 360-degree performance review, even when your engagement scores are through the roof, even when you have the most engaged workforce in your space (and you have lots of “Best Place to Work” lists and awards to prove it), your employees might still not be happy. Here’s why:

1. It’s a false equivalency. People think that because disengaged employees (there are over 70 million in the U.S. alone) are unhappy and frankly, cost the workforce a great deal of money, the ones who are engaged are happy. Not only is this bad science, it’s just lazy thinking.
2. It doesn’t mean much. There’s no proof that happy employees will do anything great for your company. While I don’t want to deny employees happiness, I’d rather have engaged employees. Those are the people who drive the numbers up — people who are passionate and maybe even a little frustrated when change doesn’t occur.
3. That’s not the point. Engaged employees are far more likely to become disengaged if employers only think about making them happy. Instead of offering additional educational opportunities, for example, employers might focus on increasing bonuses, thinking that a happy employee is an engaged employee. To an engaged employee, this might be a nice one-time bump in pay. But it won’t compensate for their investment to the organization in the way removing obstacles from their pet project just might.
4. Unforeseen consequences exist. Happy employees may be completely disengaged from the organization. Some people are very motivated by security and unemployment. Those people may be very content to fog the mirror. While these folks may not appear engaged, misinformed managers might not understand the difference between engaged employees, happy employees and employees who are just happy to have a paycheck.

So how do you guard against this myth? When you consider low employee engagement costs the U.S. economy roughly $370 billion a year, it’s important to get the focus right.

1. Learn to tell the difference between happy and engaged. Your most engaged employees might irritate you a little bit. They may propose wild ideas, get frustrated when projects are derailed and volunteer for everything. They may rarely seem super happy, because they are busy pushing the envelope. These are people you want in your organization. In fact, you want their lack of appreciation for the status quo to infect those around them.
2. Stop perpetuating the myth that happy = engaged. You don’t need to sacrifice one for the other, but stop creating an equivalency between the two. Tell your managers and your employees that while you think their happiness is important, their engagement is crucial. Listen when they tell you how to help them become more engaged.
3. Stop trying to compete. The qualities that make each workforce engaged are going to be totally unique. Zappos has worked hard to create a distinct and engaged workforce. You know what else leader Tony Hsieh has done? He’s tried to revitalize the downtown Las Vegas area. His stamp is on that project as much as it is on the way he structured the Zappos workforce. Importing programs from some other industry or business will not make your employees happy or engaged.
4. Change attitudes, not programs. When faced with poor results, many executives change the program instead of the attitude. Instead of swapping out one useless campaign for another, take the time to survey and talk to your employees before selecting a new option to increase engagement. You might be surprised at what you find out.