Running a business can appear easy from the outside, especially with new startups popping up everyday, boasting about how much fun their employees are having. Don’t get me wrong: I’ve had a lot of fun leading my company. In my experience, though, running a business is not all fun and games. It’s a lot of hard work and a lot of sleepless nights. But I’ve learned that what keeps you up year one is not the same as year three, five, or eight.

With nearly 10 years of experience leading NewsCred from a three-person team to a thriving 200-person organization, these are the actions that keep me awake today, but are essential to our success:

Retain and grow existing customers
People often mistakenly think that growing a business is dependent on new sales. But real, rapid, and sustainable growth comes from retaining the customers you’ve already won. Retention is part art, part science. While you need to make sure you deliver what you sold them and continue to innovate, you also need to carefully study trends across your customer base, identify areas where accounts may hit issues or churn, and then plan to mitigate those proactively.

Focusing on customer retention is a win-win for customers and your team. Zeroing in on customer happiness—rather than revenue—leads to more word-of-mouth-driven acquisition, upsell opportunities, and business fundamentals that you can have pride in. Many people can close deals, but it’s keeping yourself indispensable that’s the real marker of success.

See also: What Startups Should Keep in Mind When Trying to Go Global

Consider your team a constant work in progress
There are millions of hardworking people in the world, but finding those who are the right fit for your business can feel like finding a needle in a haystack. As your company grows, the demand for people will increase, and it’s up to you not to get complacent and hire “a body” vs. the greatest A-team player you’ve ever seen.

Maintaining those standards in rapid growth is challenging. It requires recognizing how each person fits into the future of your organization—not just meeting today’s needs. The truth is, your team will never truly be done, as people get promoted or change careers, so why rush?

Personally, I’ve found that during stages of such rapid growth, executives are typically right for the job for about 18 to 24 months. After that, the company scales past the executive’s ability to keep up. Some executives can certainly leapfrog and catch up to company trajectory, but most companies will have to find a more senior person. While these were some of the toughest conversations I’ve ever had, I’ve found this to be true at almost every stage of my company. The team that got us from $1 million to $5 million is different than the team that got us from $5 million to $25 million.

Relentlessly advocate for your culture
Day-to-day, it’s easy to get lost in one’s to-do list. Yet, as NewsCred has grown, I’ve found that it’s incredibly valuable for the entire organization to understand our clear vision and core set of values. By underscoring those elements of our culture every day, the to-do lists have purpose and a true north to help guide prioritization and commitment. Vision and values must be reinforced every day to be effective. One way that we keep our company culture at the forefront is with our handbook, which explains our values, our culture, and who we are as a company.

I can promise that if you prioritize these things, your business will be stronger, healthier, and will grow faster. But you may lose some shuteye on the path.