Free food, open office space, and bringing pets to work have become somewhat of a standard in the tech industry. Many people think that if your office doesn’t resemble Disneyland, you’re doing something wrong. I’ll admit—we put a lot of thought and resources into Qualtrics office spaces. From the massage chairs, to the full-service pub in our Dublin office, we’ve created workspaces that give our employees a break from routine and encourage interaction across the organization. However, these on-site office benefits don’t actually matter when it comes to engaging and retaining employees.

According to our recent Qualtrics study on millennials in the workplace, respondents ranked “free food” as one of the least important elements of company culture. Sure, catered lunches might boost employee morale once in a while, but it’s a losing strategy if you’re trying to help your employees feel like they’re an integral part of a thriving organization. If you really want to establish a company culture that facilitates higher engagement and retention, unlimited snacks and an on-site gym aren’t the answers. Here are three key ways to establish a culture that will keep your employees thriving over the long-term:

Show the opportunities for career growth
The best employees want to be challenged. If you don’t give your employees the chance to do hard things, they’ll stop trying and they’ll stop engaging. Even though this might be easier said than done, as CEO it’s my job to help people do things they didn’t know they could. This means clearing the career path to let them shine, which is why Qualtrics doesn’t just hire for “today.” We want employees who not only do their core job well, but those people who are also able to take on the responsibilities for the next five years. In other words, we want employees that have a long shelf life. The day of the “set” job description is dead. They put employees in a box and tell them to only operate within those boundaries. Job descriptions kill innovation and stifle creativity, leaving employees feeling trapped.

We want employees to feel comfortable searching for answers on their own. This not only facilitates individual employee growth—it also gives people a way to demonstrate their talents and move up within the organization. But employees also need to see tangible examples that they have this freedom to grow. Build people, give them opportunity, and then hold them up as examples so other employees know that they can do the same thing if they’re creative and take advantage of doing “hard things.”

Focus on good management
If you want to keep your best employees, you need good leaders. The best leaders are the people that step away from the traditional management model and focus on being mentors and team players. A leader’s primary role is to create an environment that encourages employees to teach and learn from each other so that everyone can achieve extraordinary things. Good managers aren’t overseers or solo performers, instead they set the stage so their entire team can perform.

In our same study on millennials we found that the quality they desired most in a boss was a willingness to be a mentor or a coach. They wanted that almost twice as much as they wanted someone who was kind, trustworthy, or even an expert in their field. Nobody wants an overseer. If you want to keep your best employees, be a mentor yourself and model that kind of “in the trenches” leadership you want to see from the people who work for you.

The organization must be fluid, not static
Part of creating a strong culture is realizing that most people don’t know exactly what they want to do. Figuring out what you want in your career is a process, and that’s okay. As CEO, my job is also to focus on creating a fluid environment where people have opportunities to move throughout the organization and find the job that best fulfills their passions. We won’t hire someone solely for the job we’re trying to fill. Instead, always hire “athletes” which we define as smart, talented people who can pivot to take on a number of different roles within the organization. Athletes are scrappy and eager to develop a variety of skills. When you can give them the flexibility to do that, everyone wins.

Establishing a fluid culture also means that company leaders need to decide what percent of talent they want to grow from the inside and what percent they want to hire from the outside. Organizations will have to do both, but we’ve learned from experience that giving existing employees the chance to grow and take on leadership roles much more inspiring than hiring from the outside.

Read all answers to the Leadership Insider question: How do you keep your best employees?

What Steve Jobs taught executives about hiring by Shahrzad Rafati, founder and CEO of BroadbandTV.

How this ex-Apple executive keeps his employees happy by Bob Borchers, senior vice president and CMO at Dolby Laboratories.

9 ways to recruit extraordinary employees by Spencer Rascoff, CEO of Zillow Group.

Why this CEO encourages failure in the workplace by Amy Errett, CEO and co-founder of Madison Reed.

Sarah Kauss: Why a pay bump isn’t the answer to employee happiness by Sarah Kauss, CEO and founder of S’well.

The one perk that will guarantee employee happiness by Ryan Harwood, CEO of PureWow.

The secret to holding on to your best employees by Amit Srivastav, president of Infinite.

3 ways to prevent your employees from quitting by Niraj Shah, CEO of Wayfair.