Would it surprise you to learn that Harvard does not have it quite right when it comes to teaching people how to lead a startup?

To be fair, Harvard's leadership courses are on the right track. But in the real world, the CEO of a rapidly growing beauty supplies technology company told me that she found herself adjusting Harvard's lessons--sometimes in surprising ways.

The CEO in question ought to know. After all, Leah Ashley of Color Me, "a leader in sonic makeup application," has a Harvard education with all the trimmings. She earned an undergraduate degree in economics, worked as a consultant at Bain and in private equity, followed by an MBA from Harvard Business School (HBS) and three years as director of beauty partnerships at Birchbox.

Last fall--with help from her business partner, Eric Jimenez, Color Me launched a product that cuts the time by 50% and boosts the quality of makeup so that women can apply it once and be confident all day.

Color Me's $54 sonic makeup application is competing with manual makeup brushes that can cost $50 to $60 and take between 10 to 30 minutes for women to apply makeup--with a morning application and two touch-ups during the day.

And Color Me is looking like it's a hit. ULTA Beauty, Sephora, and Douglas stores as well as QVC are distributing Color Me's product--an automatic sponge that pulsates at a rate of nearly 15,000 times per minute to mimic rapid finger tapping.

And industry experts expect it to sell $15 million to $20 million worth of its sonic makeup application by the end of its first year, according to WWD.

Here are her six leadership lessons and how she has tweaked them since HBS.

1. Inspiration doesn't come from the top, it comes from customers

Leaders are supposed to inspire people. But if Ashley inspires her partners and her team, it is because her customers give her inspiration.

Explained Ashley, "I let customers lead me. I stay close to them through focus groups, surveys, and customer reviews. And I convey their values clearly to my team. Customers want us to make them feel confident that they can apply their makeup quickly, that it will look good, and last all day."

2. Vision is nice, but results matter more

Leaders are also supposed to have vision. But vision seems over-rated when 99% of success has to do with disciplined execution of what is hopefully the right vision.

Ashley explained, "People talk about how leaders must be visionaries. But it's all about results and execution. Vision is still important. I am leading a sonic application movement--when people see the product, they are blown away, they become true believers."

Vision only takes you so far. "I focus on numbers; the number of women who apply makeup, the number of distribution points for our product and picking the right ones, and operational numbers like how much it will cost to design and distribute a new product and how big we will need to be to gain economies of scale in making it," Ashley said.

3. Low tech can be better than high-tech

With everyone glued to their smartphones as they barrel down the street, you would think that business success depends on smart technology.

But Ashley rejects that idea. Instead, she believes that the most important communication must be face-to-face. Some technology helps with that, other technology is an impediment.

She sees problems with email. According to Ashley, "Email can easily get ignored if you have a flooded inbox. How can you tell what is urgent? And the meaning of emails that you do read might be lost in translation."

Direct communication is better. Said Ashley, "My cofounder is always on the road and I find it best to hop on the phone, on Skype or Facetime."

4. Listening is more important than talking

Harvard sort of teaches this one. It has an idea "advocacy and inquiry" which implies that a leader must make her case and then ask questions to make sure that people buy in.

But Ashley learns more from listening. "I ask questions of our partners and listen to what they say and what they don't say. For example, when we talked with QVC about featuring our product, they did not initially ask about the personality of who would present our product. I realized that [Color Me cofounder] Eric had the vibrant personality that would be perfect," she said.

5. You can't do it all yourself

To be fair to HBS, building a startup team is something the school teaches.

The key is figuring out all the skills that the startup will need in order to be successful and to make sure that the founding team excels in them.

For Color Me, those skills are product innovation and managing the operations. "Eric and I complement each other perfectly. As an internationally known makeup artist, he understands what women want in makeup application and can develop better ways to do it. And I bring the ability to form partnerships and manage the operations of the business."

6. Leadership is simple

HBS puts a lot of emphasis on leadership but do students really need to read the thousands of pages that have been written about it?

For Ashley it's all about treating others the way she would want a leader to treat her. "I treat my team with respect. I recognize their talents and accomplishments. And I thank them for it," she said.

Follow these six leadership principles and your startup can go far.