Doug McMillon has been the CEO of Walmart for 5 years. Here are 5 lessons he's learned in that time. (WMT)

• Walmart CEO Doug McMillon has held the top spot at the world's largest retailer for five years.
• In the company's annual letter to shareholders for 2019, McMillon shared some of the lessons he has learned in that time.
• The lessons relate to leadership, risk, and employees.
• Visit Business Insider's homepage for more stories.

Doug McMillon has now been CEO at Walmart for five years.

In the company's annual letter to shareholders for 2019, McMillon shared some of the lessons he has learned in that time.

1. The first lesson relates to leadership and realizing that you can't "lead from behind." "As a leader during transformation, you have to be out in front — show that you want to learn, be curious, introduce new ideas, ask questions," McMillon writes.
2. The next relates to risk — something Walmart has had to embrace to keep up in a rapidly changing retail environment. "There is no growth without change, and there is no meaningful change without risk," McMillon writes. "So, get comfortable with an intelligent level of risk."
3. He also writes about being forward-thinking and avoiding only making decisions in the moment. "We're playing the long game. Our priority is to position our company for long-term success," McMillon writes. "History has shown us that companies that focused too much on the short term were doomed to fail."
4. He also shouts out Walmart's employees, whom the company calls associates, as becoming more comfortable with Walmart's now-speedy pace of change and even leading the charge in some cases. "People will surprise you. Several times a week, I see or hear about something creative our associates have done," McMillon writes. "It's inspiring to see their ingenuity and pace.We've always said that our people make the difference. We're certainly seeing that today."
5. The final lesson he shared was related to trust. "As we strive to make our company better, we will also look for ways to build trust by communicating the good work our people are doing and its impact," McMillon writes. "Included is the work we are doing to strengthen our culture of integrity and improve our compliance talent, processes and systems."

Read more: Walmart CEO Doug McMillon just released his annual letter to shareholders — read it here

He also highlighted the changes toward sustainability Walmart has made recently, as well as the intentions behind those decisions. 

"In our supply chain, we are eliminating waste, using more renewable energy, reducing carbon emissions and making our items and the packages they come in healthier and more sustainable," McMillon writes.

"Of course we aren't perfect. We make mistakes. But, if the world could see all of the hard-working, well-intentioned people inside our company who are making things better in their communities and in the world, I'm convinced they would be moved by it all. I am."

Walmart said in its annual report that it saw total revenue grow 3% to $514.4 billion in worldwide sales. Walmart US saw comparable sales grow by 3.6%, excluding gas, and e-commerce sales grew 40%.

SEE ALSO: Bonobos CEO reveals how the retailer is helping Walmart make a crucial strategic shift

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