With so many myths about millennials, what should employers believe and how can they confidently hire? One truth is undeniable -- millennials are discontent in their jobs.

According to Gallup, only 29% of them are engaged at work. As the largest generation in the country, that means the majority of people in the workforce are unhappy. And unhappy employees often lead to unhappy customers, declining sales and a transient staff.

But why are millennials so unhappy? It's because of the stereotypes that are perpetuated, which make hiring managers reluctant to hire millennials in the first place. And even when they do hire them, they may not be able to retain them.

We can't afford not to hire millennials, so let's uncover the truth about the top five myths that may be impeding their hiring.

1. Myth: Millennials are lazy and have bad work ethic.

Truth: Millennials want passion and purpose in their jobs.

Hiring managers often don't want to hire millennials because they think they won't do good work. But the truth is millennials aren't so different from previous generations.

In fact, millennials want to do work they are passionate about and enjoy doing. They don't just want a paycheck, but want to know that their work has a positive impact on the world around them.

Without a strong purpose, millennials won't be motivated to do their best work. When hiring millennials, make sure you emphasize how their work will affect your customers and the overall community. Give them a sense of the big picture, not just the day-to-day.

2. Myth: Millennials want free snacks and access to video games.

Truth: Millennials want good benefits.

Creating a fun and inviting workplace is important for all your employees, but that doesn't mean it needs to look like a playground. Free snacks and video games are great, but not if they come at the cost of other benefits.

Millennials want benefits that match their values and allow them to be comfortable in their lives and in the future. With an unstable retirement outlook, many millennials are eager for a 401k or other retirement program that meets their needs.

Millennials are also interested in a flexible work environment. A report by Deloitte found that millennials employed at companies with a flexible work environment are two times more like to say it has had a positive impact on their lives.

When putting together your benefits package, make sure you offer fair compensation, generous benefits and an environment where millennials feel engaged.

3. Myth: Millennials are entitled.

Truth: Millennials want to be recognized for hard work.

Many employers believe millennials to be entitled. They think millennials expect handouts even when their level of effort may be equal to everyone else's. They're seen as the "participation trophy" generation.

While it's true that millennials want recognition, they don't necessarily expect it. In fact, according to a survey by Bentley University, 84% of millennials say helping to make a positive impact on the world is more important than professional recognition.

Your millennial employees aren't looking for a pat on the shoulder every time they do something right. But when they do go the extra mile, acknowledging their hard work is a good idea.

4. Myth: Millennials lack loyalty at work.

Truth: Millennials are looking for employers who match their values.

Millennials have a reputation for job hopping, which can often be perceived as disloyal or not wanting to be a valuable member of the team. According to a survey by Capital Group, 67% of millennials say loyalty is important to them. That loyalty, though, isn't given for nothing.

Millennials want companies to treat them fairly and give them loyalty in return. Millennials won't be loyal to a company that isn't loyal to them.

If you want to gain the loyalty of your millennial employees, start by ensuring their compensation and benefits are fair. The millennial generation has been hit hard with student loan debt and other financial woes, so ensuring financial comfort is key to gaining their loyalty.

5. Myth: Millennials are always looking for their next job.

Truth: Millennials crave the opportunity to learn.

Millennials don't tend to stay in one place for long. According to Gallup, 60% of millennials say they are open to a new job opportunity. While previous generations often stay in one position for a long term, many millennials see a position as a stepping stone to another. It's not personal; it's business.

If they don't feel challenged or can't grow in their current role, millennials will seek to change jobs to advance in their careers. To retain millennial employees, make sure there is a path for advancement and provide opportunities for professional development. You will then see loyalty in return.