Great insight from Beth Gerstein, cofounder of Brilliant Earth (think diamonds).

In her Q&A with Stanford Business online, Ms. Gerstein answered the following question with an important piece of information most overlook:

What advice would you give other entrepreneurs on how to build a great business?

Test early and test often. Start on a small scale, iterate, and course-correct. This is how we were able to bootstrap the company. 

Whether you are a marketing professional or not, staying in tune with your potential customers is the name of the game. 

Certainly, social media is opening up this capability, but not all audiences you want to influence are online in ways you can keep your finger on the pulse. Therefore, use all the resources available to you (phone, focus group testing) to continue making sure your business aligns with what your customer wants and needs. 

A great idea is one thing -- applying it effectively is another. This is where becoming too micro-focused on an idea and how it plays out can cause trouble for start up companies. Rather than holding tight to your original concept, let go of it and watch it transform into what it ultimately can become.

Manage the process for growth and evolution around the idea, not the idea itself. 

Sure, selling diamonds that are ethically sourced and ultimately changing the diamond industry was the central principle, but HOW that is achieved Beth and her team allowed themselves to be open to what worked.