From Under the Hoodie: 5 Entrepreneurial Lessons From Mark Zuckerberg Five execs weigh in on what moves made the Facebook founder so successful.

Just a few years ago, the situation was looking dicey for Facebook. The company's IPO was a disaster, and its strategy on mobile appeared to be in disarray. Interestingly, there was even buzz that Mark Zuckerberg was really not cut out to be the CEO.

Related: Surprise! Mark Zuckerberg Isn't a Workaholic. Well, Not Exactly.

Well, of course, all this proved to be just another important stepping-stone in Facebook's tremendous success. After all, the company is one of the most valuable in the world, with a market cap of more than $300 billion.

So what are some of the entrepreneurial lessons here? To get valuable insight on this, I reached out to a variety of successful founders to get their feedback. Here's what they had to say:

1. 'Separate business and friendship.'

From Kristen Koh Goldstein, founder and CEO, Scalus:

"One tough lesson every founder can learn from Mr. Zuckerberg is the ability to separate business and friendship. Zuckerberg took the initiative to shed his co-founders quickly when he felt they no longer added value to Facebook. Of course, many founding CEOs put their loyalty to their friendships above the needs of the company. [But] what makes a team so good in the beginning stages -- agility and accountability -- is precisely what can break down as the business scales. When founding members become micromanagers, that undermines the rest of the team; they can prevent a company from getting to the next level. Zuckerberg and Facebook avoided this fate."

2. 'Move fast, and break things.'

From Marius Moscovici, founder and CEO, Metric Insights:

"These five simple words perfectly embody the unique philosophy that made Facebook simultaneously realize unprecedented levels of innovation and velocity. While most companies fight to preserve the current status quo that was the basis of their original success, Zuckerberg embraced the idea that "breaking things' is essential to ongoing transformation. This worked brilliantly for Facebook when it became clear that a pivot to mobile was essential to its future."

Related: Mark Zuckerberg: I Would Only Hire Someone to Work For Me If I Would Work For Them

3. 'The trick isn't adding stuff; it's taking it away.'

From Christian Turlica, founder and CEO, UP Social

"[The proposed social networking platform] HouseSYSTEM was an initial competitor of Facebook's at Harvard. Aaron Greenspan, the founder, wanted to work together with Zuckerberg. According to Greenspan, Zuckerberg responded: "It's too useful, it just does too much stuff.' When building a product, it's very important to add just the things that are necessary for one very well-defined user story. Making the product into an airplane cockpit with every single action possible is detracting at best and will, at worst, kill your product."

4. 'Think big, start small.'

From Matt Chasen, founder and CEO, uShip

"Zuck launched Facebook with a really small and easily reachable target market: college students. He then expanded beyond his early adopters when he had achieved scale, and opened it up widely -- this was a controversial move and was obviously critical in making Facebook the ubiquitous platform it is today, following the 'Think big, start small' philosophy. Get traction with a group of early adopters and then expand."

Related: These 3 Baby Photos Mark Zuckerberg Shared on Facebook Will Melt Your Heart

5. 'Stay connected to the product.'

From Kraig Swensrud, chief marketing officer, Campaign Monitor

"Mark Zuckerberg has seemingly never unattached himself from Facebook's product. No matter your role, whether you're CEO, CMO or a summer intern, it's critical to deeply understand the product. This connection to the product ensures everyone is accountable for delivering excellence. It also keeps you in touch with what your customers need."