A strong company starts with strong workers. For hiring managers, it can be hard to resist an employee from afar—much like a shiny new toy. While strategic hires outside the country can bring a fresh new perspective, sometimes looking within your own organization first to identify potential can do you better in the long run.

The promise of upward mobility is often why people take a job in the first place. One of the most common reasons people leave a job is the perception there’s no room to grow. According to Inc., people who felt like they were progressing in their career are 20% more likely to stay at their current company. They’re also more likely to contribute to positive company culture.

This is especially important to Millennials, who are more likely to leave a job than their older colleagues. While stereotypes will tell you that making a Millennial happy at work requires ping pong and snack bars, in reality most workers just want a fair wage and a promotion when they’ve earned it.

Retention isn’t just about developing strong leaders with a sense of a company’s priorities, though. If management invests in moving their employees up, they can actually save themselves some money in the greater scheme of things. Hiring a new person costs on average $2,000, which can add up overtime.

On the flip side, retaining an employee can actually increase company profits. A study by Glassdoor showed that companies that increased employee engagement investments raised profit by 10%. Many studies show that happier employees are more productive, make better decisions and are more innovative.